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

Abstract

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.

Identification of a de novo, Novel Pathogenic Variant in the Splice Region of the SOX10 Gene in an Iranian Azeri Turkish Family with Waardenburg Syndrome

“…Pathogenic variants in the SOX10 gene provide an outstanding example for studying genetic variation and phenotypic pleiotropy. Mutations in this gene can lead to the clinical manifestations of either the WS2 or the WS4 phenotype [Masood et al, 2020]. The SOX10 gene encodes the protein SOX10 (SRY [sex determining region Y] box 10), a transcription factor that regulates the neural crest [Chaoui et al, 2011].…”

Role of Twins in Waardenburg Syndrome: 1916 − present/Twin Research Reviews: MZ Twins’ Different Dermatoglyphics; Twins with Sagittal Suture Crainosynostosis; Blood Pressure in Female Twins; MZ Twins’ Education and Political Knowledge/Media Reports: Twins Created by Reciprocal In Vitro Fertilization; Reared-Apart Triplets’ Limited TV Series; Abducted Twin Infants; Winkelvoss Twins Charged by the Securities and Exchange Commission; Going From ‘Me’ to ‘We’

“…A rare case of infant male twins was presented by medical researchers from Karachi and Quetta, in Pakistan (Masood et al, 2020). The twins met the criteria for one of the four subtypes (WS-II) of Waardenburg's syndrome, that is, white forelock, heterochromia (different colored irises), hearing loss and affected first degree relative(s).…”

“…The researchers noted that for a child to be affected only one parent had to transmit the relevant gene; this mode of transmission suggests dominant inheritance, except that neither parent was affected. As Masood et al (2020) indicated, different types of gene mutations, such as insertions and deletions, may explain this syndrome. Furthermore, a recessive form of the condition (WS-II) is recognized, as I explain below.…”