Open Access

Prenatal diagnosis and genetic counseling for Waardenburg syndrome type I and II in Chinese families

  • Authors:
    • Li Wang
    • Litao Qin
    • Tao Li
    • Hongjian Liu
    • Lingcao Ma
    • Wan Li
    • Dong Wu
    • Hongdan Wang
    • Qiannan Guo
    • Liangjie Guo
    • Shixiu Liao
  • View Affiliations

  • Published online on: October 25, 2017     https://doi.org/10.3892/mmr.2017.7874
  • Pages:172-178
  • Copyright: © Wang et al. This is an open access article distributed under the terms of Creative Commons Attribution License.

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Abstract

Waardenburg syndrome (WS) is an auditory‑pigmentary disorder with varying combinations of sensorineural hearing loss and abnormal pigmentation. The present study aimed to investigate the underlying molecular pathology and provide a method of prenatal diagnosis of WS in Chinese families. A total of 11 patients with WS from five unrelated Chinese families were enrolled. A thorough clinical examination was performed on all participants. Furthermore, patients with WS underwent screening for mutations in the following genes: Paired box 3 (PAX3), melanogenesis associated transcription factor (MITF), SRY‑box 10, snail family transcriptional repressor 2 and endothelin receptor type B using polymerase chain reaction sequencing. Array‑based comparative genomic hybridization was used for specific patients whose sequence results were normal. Following identification of the genotype of the probands and their parents, prenatal genetic diagnosis was performed for family 01 and 05. According to the diagnostic criteria for WS, five cases were diagnosed as WS1, while the other six cases were WS2. Genetic analysis revealed three mutations, including a nonsense mutation PAX3 c.583C>T in family 01, a splice‑site mutation MITF c.909G>A in family 03 and an in‑frame deletion MITF c.649_651delGAA in family 05. To the best of the authors' knowledge the mutations (c.583C>T in PAX3 and c.909G>A in MITF) were reported for the first time in Chinese people. Mutations in the gene of interest were not identified in family 02 and 04. The prenatal genetic testing of the two fetuses was carried out and demonstrated that the two babies were normal. The results of the present study expanded the range of known genetic mutations in China. Identification of genetic mutations in these families provided an efficient way to understand the causes of WS and improved genetic counseling.

Introduction

Hearing loss can be present in >400 genetic syndromes. Waardenburg syndrome (WS) is the most common type of autosomal dominant syndromic hearing loss (1). It accounts for 2% of congenital deafness, is most commonly described in western populations and affects ~1 in 42,000 people. WS is characterized by congenital sensorineural hearing loss, and pigmentation defects of the eyes, hair and skin (for example, heterochromia iridum, white forelock and patchy hypopigmented skin), and dystopia canthorum (2). WS is commonly hypothesized to be caused by the absence of neuralcrest-derived melanocytes (35).

WS has been classified into four subtypes (WS1-4) based on the presence or absence of additional symptoms. WS1 and WS2 are more common than WS3 and WS4. Type 1 [Mendelian inheritance in man (MIM) no. 193500] is characterized by congenital sensorineural hearing loss, heterochromia iridis or vivid blue eyes, and depigmented patches of the skin and hair. Type 2 (MIM no. 193510) is distinguished from WS1 by the absence of dystopia canthorum. The presence of limb abnormalities separates type III WS (Klein-Waardenburg syndrome; MIM no. 148820) from type I. Type IV WS (Shah-Waardenburg syndrome disease; MIM no. 277580) exhibits features of Hirschsprung disease (an aganglionic megacolon) in addition to WS2 (5).

Currently, there are six genes, paired box 3 (PAX3), SRY-box 10 (SOX10), melanogenesis associated transcription factor (MITF), endothelin-2, endothelin receptor type B (EDNRB) and snail family transcriptional repressor 2 (SNAI2), reported to be associated with WS (6). PAX3 on chromosome 2q35 is a member of the mammalian PAX gene family and encodes a DNA-binding transcription factor expressed in neural crest cells. Human PAX3, which is 98% homologous to the murine PAX3, has four structural motifs, including a paired domain, an octapeptide sequence, a homeodomain and a Pro-Ser-Thr-rich-COOH terminus (7). PAX3 serves an important role in the migration and differentiation of melanocytes, which originate from the embryonic neural crest. The dysfunction of melanocyte migration and differentiation affects pigmentation of skin, hair and eyes, and hearing function in the cochlea. Almost all patients with WS1 and WS3 present with heterozygous mutations of PAX3 (8,9). Researchers have proposed that 15% of WS2 patients possess heterozygous mutations of MITF, which is also a transcription factor with a basic helix-loop-helix leucine zipper (b-HLH-Zip) motif. MITF has differentially expressed isoforms. The M-isoform, which is composed of nine exons (29) and is routinely studied in the WS field, encodes a protein of 419 amino acids (10). MITF is vital to the development and survival of melanocytes, osteoclasts and mast cells (11). It is estimated that the SOX10 gene accounts for ~15% of WS2 cases and 50% of WS4 cases (12). A homozygous deletion in the SNAI2 gene was described in two unrelated patients with WS2 (13) and a heterozygous EDNRB mutation has been identified in patients with WS2 (14).

Little is known about the genetic background of WS in China. In the present study, detailed analyses of the clinical manifestations and molecular mechanisms of patients with WS1/2 from five Chinese families were conducted. Prenatal diagnosis and counseling for WS was performed, as there is no specific treatment for the disease.

Materials and methods

Patients and samples

All the patients with WS were identified at Henan Provincial People's Hospital (Zhengzhou, China; March 2014 to December 2015). There were 11 patients with WS (from five families), aged 33 months-44 years old, and unaffected 10 family members who agreed to take part in the study following audiological and general physical examinations. Among the five families, family 05 was a sporadic case and the remaining families had multiple affected patients (Fig. 1). Patient characteristics are presented in Table I. The present study was approved by the ethics committee of Henan Provincial People's Hospital. Written informed consent was obtained from all adult subjects and guardians on behalf of the children, prior to clinical evaluation and blood sample collection.

Table I.

Clinical characteristics and gene variants of Waardenburg syndrome families.

Table I.

Clinical characteristics and gene variants of Waardenburg syndrome families.

Severity of HL

PedigreeGenderAgeIrisSkinWLeft earRight earGeneVariant
01-IV:5M441.85ModerateSeverePAX3c.583C>T
01-IV:7F391.87NormalNormalPAX3c.583C>T
01-V:7M10+1.85ProfoundModeratePAX3c.583C>T
02-I:1F32+1.83ProfoundModeratePAX3
02-II:1F5+1.86ProfoundProfoundPAX3
03-III:3M48+1.75SevereSevereMITFc.909G>A
03-III:9F41+1.73NormalNormalMITFc.909G>A
03- IV:8M18+1.71ProfoundProfoundMITFc.909G>A
04-I:1F28+1.75ProfoundProfoundMITFc.1060C>A
04-II:1M3+1.42SevereProfoundMITFc.1060C>A
05-II:1M2+1.41ProfoundProfoundMITFc.649_651del

[i] Iris, heterochromia iridis; skin, numerous brown freckles on the face; W, W index (2); HL, hearing loss; M, male; F, female; PAX3, paired box 3; MITF, melanogenesis associated transcription factor.

EDTA-K2 peripheral venous blood was taken from the 11 proposituses and the 10 unaffected family members (Table II). The chorionic villi sampling with ultrasonic guidance was performed for the high-risk women at 11 weeks of pregnancy. Genomic DNA was extracted using the DNA extraction kit (Tiangen Biotech Co., Ltd., Beijing, China), according to the manufacturer's protocols. The PowerPlex® 16 HS System kit (Promega Corporation, Madison, WI, USA) was used to exclude genetic contamination from the mother. The results were analyzed using ABI3130xl genetic analyzer and GeneMapper version 3.2 (both from Thermo Fisher Scientific, Inc., Waltham, MA, USA) software.

Table II.

Characteristics of the normal controls.

Table II.

Characteristics of the normal controls.

PedigreeGenderAge
01-IV8M40
01-V6M13
02-I2M31
02-II2F3
03-III5M46
03-III7F43
03-III10M43
04-I2M30
05-I1F27
05-I2M29

[i] M, male; F, female.

Clinical evaluation

Patients with WS were diagnosed according to the criteria proposed by the WS consortium (15). The diagnosis of WS can be made when ≥two major, or one major and two minor, phenotypic criteria are met. A comprehensive clinical history was taken, and audiological, neurological, ophthalmological and dermatological examinations were performed on all the subjects. The audiological and neurological examination included otoscopy, pure-tone audiometry and auditory steady-state response, immittance testing, and auditory brainstem response. Attention was paid to the color of skin, hair and iris, as well as developmental defects including dystopia canthorum and limb abnormalities. The degree of hearing loss (HL) was defined according to the pure-tone average, which was based on three frequencies (500, 1,000 and 2,000 Hz) as follows: Normal, <26 dB HL; mild, 26–40 dB HL; moderate, 41–70 dB HL; severe, 71–90 dB HL; and profound, >90 dB HL. The audiological follow-ups in infants were performed using Transient Evoked Otoacoustic Emissions and Automated Auditory Brainstem Response at 0 and 3 months.

Mutational analysis

Polymerase chain reaction (PCR) was carried out using the DNA from the patients with specific primers to amplify all exons and intron/exon boundaries of the PAX3 [National Center for Biotechnology Information reference number (NM)_181458.2], MITF-M isoform (NM_000248.2), SOX10 (NM_006941.3), and SNAI2 (NM_003068.3) and EDNRB (NM_001201397.1) genes. The primers (Table III) were designed using the online program PRIMER3 (biotools.umassmed.edu/bioapps/primer3_www.cgi). The PCR reactions were carried out in a total volume of 25 µl reaction mixture containing 40 ng genomic DNA, 2 pmol primer, 150 µmol dNTP, 0.125 units HotstarTaqDNA polymerase and 2.5 mmol MgCl2. PCR conditions consisted of an initial denaturation at 94°C for 4 min; 30 cycles of denaturation at 94°C for 30 sec, annealing at various temperatures (Table III) for 45 sec for the different primers and extension at 72°C for 45 sec; followed by a 7 min final extension at 72°C.

Table III.

Amplification and sequencing primers.

Table III.

Amplification and sequencing primers.

GeneExonForward primer sequence (5′-3′)Reverse primer sequence (5′-3′)Product size (bp)Annealing temperature (°C)
PAX31 TCACCACAGGAGGAGACTCA GAGGCCCTCCCTTACCTTC47257
2 TACGTGCTGCTGTTCTTTGC TTACGCACCTTCACAAACCTC44258
3 TCTGGTCTGCCCCTTTCTAA ATTGGGGTGATTACGTCTGG38858
4 GCTGGAGAAGGATGAGGATG CTCCAAGTGACCCAGCAAGT35157
5 TGTCTTGCAGTCGGAGAGAG GGTGGACTTCTGTGTGTCGT49258
6 AATTCGCCCAAACAACACA CAGAGAAATCGCCTGGAAGT36858
7 TGGCGATGAACTTTTGCAC GGGTGGAGAGAAAGGAAACC45158
8 TCGTCGGGCATGATGTAATA AGGAGAAATTGCCCCCTAAA35958
9 GAATTGTCCCAGCATGACCT TGCTCCAGGTCTTCCTCTTC31160
10a ACTGGCCCTGTTTCTGGTCT TGGCAAACATCACTGCACTC94358
10b CCAGTTCACATTTATTTGG CTCATAGAAAGGGTCCAC88758
MITF1 TGGTGTCTCGGGATACCTTG TGGCATCAAATAATAAACAGCA30457
2 CGTTAGCACAGTGCCTGGTA GTGGCCACAAGGACAAACTA48257
3 CATCTTGTTGCTCTGTGCCATC AAGGTGATCCACCACAAA25356
4 GACCATTATTGCTTTGGGTAAAA TGTGATCCTGAGATAATTCTCCATT34357
5 TGAGGAGATCCTGTACCTCTCTT AAAAGTTACGTCCATGAGTTGGA42557
6 GCTTTTGAAAACATGCAAGC GCTGTAGGAATCAACTCTCCTCT35058
7 CATGACCTGGAGAAGTTAATATGC AGTGTCCAACAATCCTTTTGC39856
8 CACCTGTTCCCCAAAACTA GTCAACTCCCCTATGGCTCA37258
9 CTAATGACGCGCATCTACCA TCAAGAAAACCCCTTAGGT59457
SOX101 GAGTGTTGGGGATGAAGGAA CCTGGAATTTCCCACCTTTT50058
2 AGATGGGTTTAGCTGGAGCA ACCTGGTCTTCCAGCCCTAT76558
3 GTTATTCCTTGGGCCTCACA CTTTGCCCAGTAGGATCAGC68657
4-a CATGCTGCCAAAATGTGAAA ATAGGGTCCTGAGGGCTGAT67856
4-b AGCCCAGGTGAAGACAGAGA TCTGTCCAGCCTGTTCTCCT56157
EDNRB1 CATTTCCTGGTTCCCTGACT ACCAAAACCAAAGTGCCAAT36158
2 CTTTTGAGCGTGGATACTGG AGGGAGCTAAAGGGAAGCTC74858
3/4 CCCAACACACTTTCCTGTCC TTCTTGCAGCTTGAGTCATTG81657
5 TGTTCAGTAAGTGTGGCCTGA CAAGAAAAAGGAAATATGCTCTGG43256
6 CACTTCGGTTCCACTTCACA CTTCCCTGTCCCTCTCAACA46658
7 GAGGGGGACACAGACAGAGA GCAGTAGGGAGTGGCTGACT49357
8 AAGAGGGAAAATAAAAGAGCACTG TTCTTTCCATGCCGTAAACA46657
SNAI21 GCTGTGATTGGATCTTTCTTGC TGTAAGCTCCCTTTCAGGACAC44956
2 TGTGTGTATACTTGCGTGTGG CTTCATGCAAATCCAACAGC70058
3 ATTTCTGTATGATTGGCAGCAG GCTTCGGAGTGAAGAAATGC47156

[i] PAX3, paired box 3; MITF, melanogenesis associated transcription factor; SOX10, SRY-box 10; EDNRB, endothelin receptor type B; SNAI2, snail family transcriptional repressor 2; bp, base pairs.

PCR fragments were purified and sequenced in each direction on an ABI3130xl DNA sequencer, with a BigDye Terminator Cycle Sequencing kit (Thermo Fisher Scientific, Inc.), with the same primers used for PCR. The raw sequence data were aligned with the wild-type sequence using the GeneTool program version 2.0 (Syngene Europe, Cambridge, UK). Following the identification of mutations of the WS genes in the propositus, samples from the related family members and normal controls were further screened for the mutations.

Array-based comparative genomic hybridization (aCGH)

a-CGH was performed on patients whose sequence results were normal, a-CGH was carried out by using the SurePrint G3 Human CGH Microarray 8×60K kit (Agilent Technologies, Inc., Santa Clara, CA, USA). For each sample, 500 ng genomic DNA was used for each a-CGH experiment. DNA was labeled by direct incorporation of Cy5-deoxyuridine triphosphate (dUTP) and Cy3-dUTP, according to the Agilent protocol. Labeled DNA was purified and then hybridized to the arrays. Following performance of the hybridization step and the recommended washes, the arrays were scanned with a SureScan Dx Microarray scanner and analyzed using CytoGenomics 2.9 (both from Agilent Technologies, Inc., Santa Clara, CA, USA).

Results

Clinical findings

According to the diagnostic criteria for WS, five cases (IV:5, IV:7 and V:7 in family 01, I:1 and II:1 in family 02) were diagnosed as WS1, while the other six cases (III:3, III:9 and IV:8 in family 03, I:1 and II:1 in family 04, II:1 in family 05) were WS2. Among these patients, deafness and heterochromia iridum were the most frequent features, and nine patients exhibited sensorineural hearing impairment varying from moderate to profound. Additionally, the characteristic brilliant blue irides (unilateral or bilateral heterochromia irides), were observed in 6 patients. Each of the WS1 cases exhibited dystopia canthorum, and three of them (01-V7, IV7 and 02-II1) also presented with broad nasal roots. A total of 3 patients in family 03 had numerous brown freckles on the faces. Patchy skin depigmentation was only observed in family 05. Other clinical features, a white forelock and hypopsia for example, were not observed in the present study (Table I). Representative clinical findings and the typical characteristics of these WS cases were illustrated in Fig. 2.

Identification of mutations

Six variants were identified in these proposituses. A heterozygous nonsense mutation c.583C>T in PAX3 exon 4 was identified in 3 affected members of family 01, resulting in a premature termination codon at the 195th nucleotide within the octapeptide domain of the PAX3 protein (Fig. 3A). The sequencing and a-CGH assays failed to detect the mutation in family 02.

Three heterozygous mutations in MITF were identified in these WS2 patients, including splice-site, missense and deletion mutations. The splice-site mutation c.909G>A was identified in family 03 (Fig. 3B), which has been reported by Brenner et al (16). Unlike the previous splicing variants reported, the mutation did not destroy the acceptor or donor splicing sites, but created a new splice acceptor site. The variant c.1060C>A (p.L354I) in exon 9 was found in family 04, which led to a substitution from Leu to Ile at the 354th amino acid (Fig. 3C). An in-frame deletion c.649_651delGAA, del (R217) mutation was identified in family WS05, which removed one of a run of four arginines in the basic domain (Fig. 3D). The mutations (c.583C>T in PAX3, c.909G>A and c.649_651delGAA in MITF) identified in these patients were not observed in any other unaffected family members. Other synonymous substitutions were, c.927T>C in SOX10 (family 03) and c.831A>G in EDNRB (family 04).

Prenatal diagnosis and follow-up

Following identification of the genotype of the probands and their parents, prenatal genetic diagnosis was performed for the two fetuses of family 01 and family 05, as a carrier, the couples have a 50% chance of affected offspring. DNA was extracted from chorionic villi samples and mutations of the PAX3/MITF gene were detected. The prenatal genetic diagnosis revealed the two babies were normal for the genes examined (data not shown). Furthermore, the audiological follow-ups between 0 and 6 months revealed hearing was within normal thresholds.

Discussion

WS may not be a rare disease in China as reported previously, up to now, >50 cases had been reported (1719). More patients may be identified in special schools for children with hearing loss, although a large-scale, population-based study is required to confirm this. The syndrome involves a number of highly variable clinical manifestations. A previous study suggested that sensorineural deafness is the most frequent feature of WS (60% in WS1 and 90% in WS2) (20). In the present study, the majority of the patients (81.81%; 9/11) exhibited bilateral sensorineural hearing loss, ranging from moderate deafness to a progressive profound hearing loss. The syndrome exhibits a highly variable phenotype within families and incomplete penetrance. The affected individuals may exhibit multiple symptoms; however, certain patients exhibit few symptoms of WS, including IV:7 and V:7 in family 01. In addition, the propositus's father in family 05 was a healthy subject, despite the fact that he carried the same mutation as propositus. The father exhibited only a skin pigmentary disorder on both hands and is not a patient with WS according to the diagnostic criteria. It was speculated that the symptom may be associated with the genetic abnormalities. The skin pigmentation disorder is a rare clinical feature in WS families in China. This supported the results of the study by Liu et al (21) that skin pigmentation disorders are less frequent. Conversely, features including deafness or facial freckles are relatively common, which makes the clinical diagnosis difficult, particularly for WS2 (IV:8 from family 03). Therefore, molecular genetic analyses of WS genes are important diagnostic steps to explain the molecular cause of WS, and facilitate genetic counseling of affected patients and their families.

Currently six genes have been identified to be associated with WS. To date, >280 mutations in these genes have been reported in patients with WS (grenada.lumc.nl/LOVD2/WS). PAX3 mutations account for the majority of WS1 and WS3; however, few of them are recurrent. Missense and nonsense mutations, frameshifts, small in-frame insertions or deletions, and splice alterations of the PAX3 gene have been reported in patients with WS1. Altogether, ~50% of the mutations are missense and 50% are truncating variations. The majority of the novel mutations in PAX3 are localized in exons 2–6 and therefore influence functionally relevant domains. In the present study, the PAX3 mutation c.583C>T in exon 4 was detected within family 01 cases, which led to premature termination at the 195th amino acid and was void of functional domains. This mutation has been previously reported by Read et al (2). No mutation was identified in family 02 by PAX3 exon sequencing which cannot reliably detect whole exon or whole gene copy number alterations. Drozniewska et al (22) reported a patient with a de novo 2q36.1 deletion of 862 kb, including the PAX3 gene, which indicates that deletion or duplication screening is indispensable for the molecular genetic diagnosis of WS. Neither deletion nor duplication was observed in family 02 by a-CGH. It's possible that the mutation remains to be identified as: i) Mutations deep in introns or promoter regions were not sequenced; and ii) mutations in other genes may be involved in pathogenesis (23,24).

Currently, ~30% of WS2 cases can be explained at the molecular level. It is estimated that MITF mutations occur in ~15% of WS2. Through binding to DNA sequences, MITF regulates melanocyte differentiation and the transcription of several melanocyte-specific genes. Mutant MITF proteins are thought to possess defects in homo- or heterodimerization, and DNA binding through their basic regions. Point mutations are not evenly scattered along the gene, the majority of them are located in exons 7 and 8 that correspond to the b-HLH-Zip motifs. Interruption of the b-HLH-Zip domain decreases the ability of the mutant MITF protein to bind to the CATGTG core DNA sequence in the human tyrosinase promoter (25). Wildhardt et al (26) reported a patient with WS2 carrying two MITF mutations (missense mutation and small deletion) within the same copy of the gene. In the present study, three MITF mutations, c.909G>A (p.Thr303Thr), c.649_651delGAA and c.1060C>A (p.L354I) were identified. The synonymous mutation c.909G>A was demonstrated to create a novel splice acceptor site that removes the 52 bps from the mRNA and results in the introduction of seven novel amino acids with premature termination and loss of the terminal 133 amino acids (16). The in-frame deletion c.649_651delGAA, del (R217) mutation in exon 7 was identified in family WS05, which removes one of four arginines in the basic domain. Conservation analyses revealed that the Arg residues at 217 in MITF are conserved across humans, mice, chickens, cows, and dogs. The mutation had been previously reported in a Caucasian family (8). In the family, the mother and son exhibited severe congenital sensorineural hearing loss and pigmentary disorder. The phenotype resembles the albinism-deafness syndrome of Tietz (MIM no. 103500) to an increased extent compared with classical Waardenburg syndrome, which is different from the patients in the present study. It can be speculated that there is interplay between genetic modifiers, environmental factors and stochastic events, in addition to the mutation itself. The mutation c.649_651delGAA in the MITF gene may be a hot spot for 7 cases reported in the mutation database.

Variant c.1060C>A (L354I) was identified in WS04. The mutation p.L354I fell outside of the important MITF domain, and was predicted to exhibit a ‘benign’ or ‘tolerated’ effect by the PolyPhen-2 (http://tiddlyspace.com/bags/icgc_public/tiddlers/PolyPhen2), and SIFT (http://sift.jcvi.org) software, respectively.

Simultaneously, the child inherited it from his unaffected father, while his affected mother did not carry the same mutation. Other variants of MITF have been reported, including: c.20A>G(p.Tyr7Cys), c.332C>T(p.Ala111Val), c.483A>T(p.Gln161His), c.608G>A (p.Arg203 Lys) and c.892T>C (p.Ser298Pro), all of which are thought to be likely neutral variants or the Single Nucleotide Polymorphism database (5,8,19).

The above mutations (c.583C>T in PAX3 and c.909G>A in MITF) were first identified in the Chinese population. These mutations in the WS genes enable prenatal diagnosis to be performed for the high-risk fetus. If one of the parents carries a dominant altered WS gene, there is a 50% chance that the children will inherit the disease. Preimplantation genetic diagnosis (PGD) is an alternative to prenatal diagnosis and is an almost safe, harmless, non-invasive and ethically acceptable procedure (27). However, PGD could not be easily obtained by the families for economic reasons. Invasive prenatal diagnosis may be another effective means of preventing recurrence of genetic disease. Therefore, prenatal diagnosis for the two families (01 and 05) was performed. The results demonstrated that the two fetuses were normal, which was confirmed by audiological follow-ups. However, a positive test result may be derived from a patient exhibiting a normal phenotype despite the presence of mutations as there may be reduced penetrance. For this reason, it is important to discuss these issues during genetic counseling. In the future, non-invasive prenatal diagnosis of WS by examination of cell-free fetal DNA in maternal blood will be performed.

In conclusion, the results of the present study expand the database of known mutations in Chinese patients with WS. Certain cases remain unexplained at the molecular level, which require further study. The exact description of the mutations responsible for the WS type is of importance in genetic counseling of patients with WS and their families.

Acknowledgements

The present study was supported by the National Natural Science Foundation of China (grant no. 81170581), the Science and Technology Project of Henan Province (grant no. 2010031114), and the Medical Science and Technology Project of Henan Province (grant no. 87).

References

1 

Zaman A, Capper R and Baddoo W: Waardenburg syndrome: More common than you think! Clin Otolaryngol. 40:44–48. 2015. View Article : Google Scholar : PubMed/NCBI

2 

Read AP and Newton VE: Waardenburg syndrome. J Med Genet. 34:656–665. 1997. View Article : Google Scholar : PubMed/NCBI

3 

Baxter LL, Hou L, Loftus SK and Pavan WJ: Spotlight on spotted mice: A review of white spotting mouse mutants and associated human pigmentation disorders. Pigment Cell Res. 17:215–224. 2004. View Article : Google Scholar : PubMed/NCBI

4 

Mollaaghababa R and Pavan WJ: The importance of having your SOX on: Role of SOX10 in the development of neural crest-derived melanocytes and glia. Oncogene. 22:3024–3034. 2003. View Article : Google Scholar : PubMed/NCBI

5 

Pingault V, Ente D, Dastot-Le Moal F, Goossens M, Marlin S and Bondurand N: Review and update of mutations causing Waardenburg syndrome. Hum Mutat. 31:391–406. 2010. View Article : Google Scholar : PubMed/NCBI

6 

Song J, Feng Y, Acke FR, Coucke P, Vleminckx K and Dhooge IJ: Hearing loss in Waardenburg syndrome: A systematic review. Clin Genet. Jun 22–2016.(Epub ahead of print). View Article : Google Scholar

7 

DeStefano AL, Cupples LA, Arnos KS, Asher JH Jr, Baldwin CT, Blanton S, Carey ML, da Silva EO, Friedman TB, Greenberg J, et al: Correlation on between Waardenburg syndrome phenotype and genotype in a population of individuals with identified PAX3 mutations. Hum Genet. 102:499–506. 1998. View Article : Google Scholar : PubMed/NCBI

8 

Tassabehji M, Newton VE, Liu XZ, Brady A, Donnai DK, ajewska-Walasek M, Murday V, Norman A, Obersztyn E, Reardon W, et al: The mutational spectrum in Waardenburg syndrome. Hum Mol Genet. 4:2131–2137. 1995. View Article : Google Scholar : PubMed/NCBI

9 

Wollnik B, Tukel T, Uyguner O, Ghanbari A, Kayserili H, Emiroglu M and Yuksel-Apak M: Homozygous and heterozygous inheritance of PAX3 mutations causes different types of Waardenburg syndrome. Am J Med Genet A. 122A:42–45. 2003. View Article : Google Scholar : PubMed/NCBI

10 

Shibahara S, Takeda K, Yasumoto K, Udono T, Watanabe K, Saito H and Takahashi K: Microphthalmia-associated transcription factor (MITF): Multiplicity in structure, function, and regulation. J Invest Derm Symp Proc. 6:99–104. 2001. View Article : Google Scholar

11 

Grill C, Bergsteinsdottir K, Ogmundsdóttir MH, Pogenberg V, Schepsky A, Wilmanns M, Pingault V and Steingrimsson E: MITF mutations associated with pigment deficiency syndromes and melanoma have different effects on protein function. Hum Mol Genet. 22:357–4367. 2013. View Article : Google Scholar

12 

Tassabehji M, Newton VE and Read AP: Waardenburg syndrome type 2 caused by mutations in the human microphthalmia (MITF) gene. Nat Genet. 8:251–255. 1994. View Article : Google Scholar : PubMed/NCBI

13 

Sánchez-Martín M, Rodríguez-García A, Pérez-Losada J, Sagrera A, Read AP and Sánchez-García I: SLUG (SNAI2) deletions in patients with Waardenburg disease. Hum Mol Genet. 11:3231–3236. 2002. View Article : Google Scholar : PubMed/NCBI

14 

Jabeen R, Babar ME, Ahmad J and Awan AR: Novel mutations of endothelin-B receptor gene in Pakistani patients with Waardenburg syndrome. Mol Biol Rep. 39:785–788. 2012. View Article : Google Scholar : PubMed/NCBI

15 

Farrer LA, Grundfast KM, Amos J, Arnos KS, Asher JH Jr, Beighton P, Diehl SR, Fex J, Foy C, Friedman TB, et al: Waardenburg syndrome (Ws) type-I is caused by defects at multiple Loci, one of which is near alpp on chromosome-2-1st report of the Ws consortium. Am J Hum Genet. 50:902–913. 1992.PubMed/NCBI

16 

Brenner L, Burke K, Leduc CA, Guha S, Guo J and Chung WK: Novel splice mutation in microthalmia-associated transcription factor in Waardenburg Syndrome. Genet Test Mol Biomarkers. 15:525–529. 2011. View Article : Google Scholar : PubMed/NCBI

17 

Chen H, Jiang L, Xie Z, Mei L, He C, Hu Z, Xia K and Feng Y: Novel mutations of PAX3, MITF, and SOX10 genes in Chinese patients with type I or type II Waardenburg syndrome. Biochem Biophys Res Commun. 397:70–74. 2010. View Article : Google Scholar : PubMed/NCBI

18 

Jiang L, Chen H, Jiang W, Hu Z, Mei L, Xue J, He C, Liu Y, Xia K and Feng Y: Novel mutations in the SOX10 gene in the first two Chinese cases of type IV Waardenburg syndrome. Biochem Biophys Res Commun. 408:620–624. 2011. View Article : Google Scholar : PubMed/NCBI

19 

Yang S, Dai P, Liu X, Kang D, Zhang X, Yang W, Zhou C, Yang S and Yuan H: Genetic and phenotypic heterogeneity in Chinese patients with Waardenburg syndrome type II. PLoS One. 8:e771492013. View Article : Google Scholar : PubMed/NCBI

20 

Nayak CS and Isaacson G: Worldwide distribution of Waardenburg syndrome. Ann Oto Rhinol Laryn. 112:817–820. 2003. View Article : Google Scholar

21 

Liu X, Newton V and Read A: Hearing loss and pigmentary disturbances in Waardenburg syndrome with reference to WS type II. J Laryngol Otol. 109:96–100. 1995. View Article : Google Scholar : PubMed/NCBI

22 

Drozniewska M and Haus O: PAX3 gene deletion detected by microarray analysis in a girl with hearing loss. Mol Cytogenet. 7:302014. View Article : Google Scholar : PubMed/NCBI

23 

Berlin I, Denat L, Steunou AL, Puig I, Champeval D, Colombo S, Roberts K, Bonvin E, Bourgeois Y, Davidson I, et al: Phosphorylation of BRN2 modulates its interaction with the Pax3 promoter to control melanocyte migration and proliferation. Mol Cell Biol. 32:1237–1247. 2012. View Article : Google Scholar : PubMed/NCBI

24 

Degenhardt KR, Milewski RC, Padmanabhan A, Miller M, Singh MK, Lang D, Engleka KA, Wu ML, Li J, Zhou D, et al: Distinct enhancers at the Pax3 locus can function redundantly to regulate neural tube and neural crest expressions. Dev Biol. 339:519–527. 2010. View Article : Google Scholar : PubMed/NCBI

25 

Takeda K, Takemoto C, Kobayashi I, Watanabe A, Nobukuni Y, Fisher DE and Tachibana M: Ser298 of MITF, a mutation site in Waardenburg syndrome type 2, is a phosphorylation site with functional significance. Hum Mol Genet. 9:125–132. 2000. View Article : Google Scholar : PubMed/NCBI

26 

Wildhardt G, Zirn B, Graul-Neumann LM, Wechtenbruch J, Suckfüll M, Buske A, Bohring A, Kubisch C, Vogt S, Strobl-Wildemann G, et al: Spectrum of novel mutations found in Waardenburg syndrome types 1 and 2: Implications for molecular genetic diagnostics. Bmj Open. 3:pii: e001917. 2013. View Article : Google Scholar : PubMed/NCBI

27 

Millan JM, Aller E, Jaijo T, Grau E, Beneyto M and Najera C: Genetic counselling in visual and auditory disorders. Arch Soc Esp Oftalmol. 83:689–702. 2008.(In Spanish). PubMed/NCBI

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January 2018
Volume 17 Issue 1

Print ISSN: 1791-2997
Online ISSN:1791-3004

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APA
Wang, L., Qin, L., Li, T., Liu, H., Ma, L., Li, W. ... Liao, S. (2018). Prenatal diagnosis and genetic counseling for Waardenburg syndrome type I and II in Chinese families. Molecular Medicine Reports, 17, 172-178. https://doi.org/10.3892/mmr.2017.7874
MLA
Wang, L., Qin, L., Li, T., Liu, H., Ma, L., Li, W., Wu, D., Wang, H., Guo, Q., Guo, L., Liao, S."Prenatal diagnosis and genetic counseling for Waardenburg syndrome type I and II in Chinese families". Molecular Medicine Reports 17.1 (2018): 172-178.
Chicago
Wang, L., Qin, L., Li, T., Liu, H., Ma, L., Li, W., Wu, D., Wang, H., Guo, Q., Guo, L., Liao, S."Prenatal diagnosis and genetic counseling for Waardenburg syndrome type I and II in Chinese families". Molecular Medicine Reports 17, no. 1 (2018): 172-178. https://doi.org/10.3892/mmr.2017.7874