Familial nonsyndromic hearing loss with incomplete partition type II caused by novel DSPP gene mutations

AbstractBackground: Familial nonsyndromic hearing loss (NSHL) with incomplete partition type II (IP-II) is a very rare condition.Aims/Objectives: To determine the audiological feature, inheritance patterns and genetic etiology of familial NSHL with IP-II in a Chinese family with eight family members.Material and methods: Clinical data were collected from all eight family members, selected deafness genes were sequenced in proband and whole genome sequencing of seven family members was performed.Results: The proband were a pair of male nonidentical twins (III:1, III:2). Three patients in this family, including the twins and their father (II:1), were diagnosed with bilateral NSHL with IP-II, and no mutation was found in the genes of SLC26A4, GJB2, GJB3, mitochondrial 12S rRNA, and MITF. Whole genome sequencing data indicated de novo mutations of the gene DSPP, c.3085A > G and c.3087C > T, which resulted in p.N1029D and co-segregated with deafness phenotype, were the underlying genetic etiology.Conclusion and...