Case of Waardenburg Shah syndrome in a family with review of literature

Auditory and speech outcomes of cochlear implantation in patients with Waardenburg syndrome: a meta-analysis

Objective

This study aims to assess the potential efficacy of cochlear implantation as a treatment for patients with Waardenburg syndrome (WS) and to guide clinical work by comparing the effect of auditory and speech recovery after cochlear implantation in patients with WS and non-WS.

Methods

PubMed, the Cochrane Library, CNKI, and Wanfang Data were sources for retrieving literature on cochlear implantation in WS, and clinical data meeting the inclusion criteria were meta-analyzed using RevMan5.41.

Results

A total of nine articles were included in this study, including 132 patients with WS and 815 patients in the control group. Meta-analysis showed that there are no significant differences in the scores for categories of audit performance (CAP), speech intelligibility rating (SIR), and parents' evaluation of aural/oral performance of children (PEACH) between the WS group and the control group.

Conclusion

Cochlear implantation demonstrates comparable auditory and speech recovery outcomes for WS patients and non-WS patients.

A novel variant of the SOX10 gene associated with Waardenburg syndrome type IV

BACKGROUND

Waardenburg syndrome (WS) is a rare genetic disorder characterized by varying degrees of sensorineural hearing loss and accumulated pigmentation in the skin, hair and iris. The syndrome is classified into four types (WS1, WS2, WS3, and WS4), each with different clinical phenotypes and underlying genetic causes. The aim of this study was to identify the pathogenic variant in a Chinese family with Waardenburg syndrome type IV.

METHODS

The patient and his parents underwent a thorough medical examination. We applied whole exome sequencing to identify the causal variant on the patient and other family members.

RESULTS

The patient presented with iris pigmentary abnormality, congenital megacolon and sensorineural hearing loss. The clinical diagnosis of the patient was WS4. The whole exome sequencing (WES) revealed a novel variant (c.452_456dup) in the SOX10 gene, which could be responsible for the observed pathogenic of WS4 in this patient. Our analysis suggests that this variant produces a truncated protein that contributes to the development of the disease. The genetic test confirmed the diagnosis of WS4 in the patient from the studied pedigree.

CONCLUSIONS

This present study demonstrated that genetic test based on WES, an effective alternative to regular clinical examinations, helps diagnose WS4. The newly identified SOX10 gene variant can expand the understanding of WS4.

Waardenburg-Shah syndrome rare and challenging case report from Somalia

Introduction and importance

Waardenburg-Shah disorder could be an uncommon autosomal recessive inherited ailment characterized by aganglionic megacolon with a high mortality rate. Babies born with Waardenburg syndrome may have typical features of hair, skin and eye pigmentary abnormalities, and hearing loss. Here we present a case with typical presentation of Waardenburg Shah syndrome.

Case presentation

This is a case of neonatal intestinal obstruction caused by a rare syndrome known as Waardenburg-Shah syndrome, with clinical manifestations of abdominal distension, bilious vomiting, and a history of delayed meconium passage with a family history of variant forms of this syndrome. The patients underwent first laparotomy, which found no atresia.post op colongarphy revealed a narrowed colon. Then reoperated, and a biopsy was taken and opened ileostomy. The pathology result showed gangilion negative. The patient was lost due to uncontrollable sepsis at the age of 2 months.

Clinical discussion

Waardenurg syndrome is a congenital audito-pigmentary syndrome first described in 1951.Waardenurg syndrome is classified into four types, WS1 to WS4, and they share the common presence of congenital sensoneural hearing loss and pigmentary defects. The diagnosis of WS has major and minor criteria. The definitive management of this disorder involves surgical removal of aganglionic segment of the bowel and connecting functioning gangilioic bowel to the anus.

Conclusion

Shah-Waardenburg syndrome TYPE-4 is a relatively unusual syndrome characterized by a higher prevalence of whole colonic aganglionosis with or without small bowel involvement, resulting in substantial morbidity and mortality in the neonatal age range.

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Waardenburg syndrome is a very rare genetically inherited disorder with a variety of manifestations characterized by agangilionic megacolon with high mortality rate with typical pigmentary abnormalities

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the definitive management of this disorder involves surgical removal of agangilionic segment of the bowel and connecting functioning gangilionic bowel to the anus

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These children's predicaments are exacerbated by inadequate health-care facilities. For better results, a comprehensive approach to these issues is required.

A De Novo MITF Deletion Explains a Novel Splashed White Phenotype in an American Paint Horse

Splashed white is a coat color pattern in horses characterized by extensive white patterning on the legs, belly, and face often accompanied by blue eyes and deafness. Three mutations in microphthalmia-associated transcription factor (MITF) and two mutations in Paired Box 3 (PAX3) have been identified that explain splashed white patterns (SW1-SW5). An American Paint Horse stallion with a splashed white phenotype and blue eyes, whose parents were not white patterned, was negative for the 5 known splashed white variants and other known white spotting alleles. This novel splashed white phenotype (SW6) was hypothesized to be caused by a de novo mutation in MITF or PAX3. Analysis of whole-genome sequencing using the EquCab3.0 reference genome for comparison identified an 8.7 kb deletion in MITF on ECA16 (NC_009159.3:g.21551060-21559770del). The deletion encompassed part of intron 7 through the 3' UTR of exon 9 of MITF, including the helix-loop-helix DNA-binding domain (ENSECAT00000006375.3). This variant is predicted to truncate protein and impair binding to DNA. Sanger sequencing confirmed the stallion was heterozygous for the MITF deletion. No single nucleotide polymorphisms (SNPs) or structural variants were identified in PAX3 or any of the other candidate genes that were unique to the stallion or predicted to affect protein function. Genotyping five of the stallion's splashed white offspring, including one all white foal, found that they were also heterozygous for the deletion. Given the role of MITF in producing white pattern phenotypes, and the predicted deleterious effect of this mutation, this 8.7 kb deletion is the likely causal variant for SW6.

Frameshift variant in MITF gene in a large family with Waardenburg syndrome type II and a co-segregation of a C2orf74 variant

Waardenburg syndrome (WS) is a hereditary disorder affecting the auditory system and pigmentation of hair, eyes, and skin. Different variants of the disease exist with the involvement of mutation in six genes. The aim of the study is to identify the genetic defects underlying Waardenburg syndrome in a large family with multiple affected individuals. Here, in this study, we recruited a large family with eleven affected individuals segregating WS type 2. We performed whole genome SNP genotyping, whole exome sequencing and segregation analysis using Sanger approach. Whole genome SNP genotyping, whole exome sequencing followed by Sanger validation of variants of interest identified a novel single nucleotide deletion mutation (c.965delA) in the MITF gene. Moreover, a rare heterozygous, missense damaging variant (c.101T>G; p.Val34Gly) in the C2orf74 has also been identified. The C2orf74 is an uncharacterized gene present in the linked region detected by DominantMapper. Variants in MITF and C2orf74 follows autosomal dominant segregation with the phenotype, however, the variant in C2orf74 is incompletely penetrant. We proposed a digenic inheritance of variants as an underlying cause of WS2 in this family.

MITF p.Arg217Thr Variant Identified in a Han Chinese Family with Tietz/Waardenburg Syndrome

Waardenburg syndrome (WS) is a group of rare genetic disorders characterized by hearing loss, changes in coloring of hair, skin, and eyes, and alterations in the shape of the face. Tietz syndrome is another rare disorder which presented similar phenotypes to WS. Patients with Tietz/Waardenburg syndrome often present with pale blue eyes, albino skin, and distinctive hair coloring, such as a patch of white hair or hair that prematurely turns gray. At present, more than six candidate genes are responsible for four types of Waardenburg syndrome and Tietz syndrome. This study is aimed at identifying the pathogenic gene variants in a three-generation Han Chinese family with hearing loss, blue-gray iris, albino skin, and white hair. In order to discover the molecular genetic lesion underlying the disease phenotype, whole exome sequencing in the proband, with Tietz/Waardenburg syndrome phenotypes, of a Han Chinese family from HeBei, China, was conducted. A novel heterozygous c.650G>C/p.Arg217Thr variant in melanocyte inducing transcription factor (MITF) was identified. Sanger sequencing further validated that this mutation existed in three affected individuals and absent in healthy family members. Bioinformatics analysis predicted that this mutation was deleterious. Our study further identified the genetic lesion of the family. Simultaneously, our study may also contribute to genetic counseling, embryonic screening of in vitro fertilized embryos, and prenatal genetic diagnosis of patients with Tietz/Waardenburg syndrome, especially for the proband, unmarried and unpregnant women, to reduce familial transmission in this Han Chinese family.

Waardenburg Syndrome Type-II in Twin Siblings: An Unusual Audio-Pigmentary Disorder

Waardenburg syndrome (WS) is an interesting inherited audio-pigmentary disorder. The syndrome shows no gender, racial, or ethnic predilection. This unique disorder is characterized by pigmentary abnormalities, deafness, and neural crest-derived tissue defect. WS can be recognized by some specific clinical features that appear after birth; not all affected individuals possess all the clinical features. It has four clinical sub types based on the mutant gene and characteristic morphology. These morphological features are broad nasal root, white forelock, the difference in the colour of eyes, congenital leukoderma, and sensorineural deafness. We report an interesting case of WS in twin boys who fulfill the criteria of WS-II. Our cases have four major criteria (white forelock, heterochromia, sensorineural hearing loss, first degree relative with WS), and 1 minor criterion to establish the diagnosis of WS-II. Most clinical features of WS-II except sensorineural deafness are benign and do not need any intervention but severe deafness can be a serious problem. The current report is unique and is a rare case of WS in twin infants. We present this case for its rarity, relative paucity of literature, and also to emphasize the clinical presentation of this extremely rare disease in twins.

[Ophthalmologic manifestations of Waardenburg syndrome]

The Waardenburg syndrome is a group of rare genetic diseases, which clinical manifestations include neurosensory hearing loss, diminished pigmentation of forelock in the frontal region, iris heterochromia, medial canthus dystopia, and the presence of such changes in first-line relatives. The article presents a clinical case of type I Waardenburg syndrome, which developed de novo in a family. This case is unique in its combination of complete bilateral iris heterochromia and impaired choroidal pigmentation. The choroid did not only have hypopigmentation zones, but also large areas of hyper- and depigmentation. Such choroidal changes in Waardenburg patients has not been described in literature before. The diagnosis was confirmed by OCT of the anterior and posterior segments, angio-OCT, fluorescein angiography, indocyanine green angiography, fundus autofluorescence, and electrophysiological studies. The main ophthalmologic diagnostic criterion of Waardenburg syndrome in the present case, beside iris heterochromia, was the detection of iris thickness changes in hyper- and hypopigmentation areas with completely preserved structural and functional properties of the retina and choroid.

Whole genome genotyping mapped regions on chromosome 2 and 18 in a family segregating Waardenburg syndrome type II

Objectives

Waardenburg syndrome is a rare genetic disorder. It is characterized by sensorineural hearing impairment and pigment defects of the skin, hair and iris. In some cases abnormalities in the tissues derived from neural crest have also been reported. Mutations in several genes have been reported as an underlying cause of Waardenburg syndrome. Objective of this study is to identify the chromosomal region(s) associated with Waardenburg syndrome in an extended Saudi family.

Methods

Genomic DNA was extracted from fifteen individuals of a Saudi family segregating Waardenburg syndrome. Whole genome SNP genotyping was performed to identify common identity by descent chromosomal region(s) shared by affected individuals.

Results

Pedigree analysis confirm autosomal dominant inheritance of Waardenburg syndrome type II in a family. Whole genome SNP genotypes were analyzed using AutoSNPa and DominantMapper tools. Shared identity by descent chromosomal regions were identified on chromosome 2 and chromosome 18. Regions were checked for known Waardenburg syndrome genes. No known gene is present in both regions.

Conclusions

In summary, we identified novel chromosomal regions associated with Waardenburg syndrome type II in a Saudi family. Deep sequencing of a complete candidate regions are required to identify the gene underlying Waardenburg syndrome in this family.