Identifying novel putative genes linked to stuttering in highly
multiplex Indian families using exome sequencing
Abstract
Abstract Stuttering is a complex speech disorder and heritability of
this trait is persuasive, with multiple afflicted families showing
phenotypic segregation across generations, yet no conclusive genetic
etiology could be identified. Analyzing multiplex families using exome
sequencing(ES) may help in identification of putative genes and scope
for understanding the mutational burden for speech implicated pathways.
In this study ES was performed in six individuals from two clinically
well characterized, multiple affected, south Indian families (STU-65 and
STU-66) showing stuttering across five generations. From ES to variant
prioritization, a sequential bioinformatics approach was implemented to
search for putative gene targets. In the two multiplex families studied,
ES data analysis resulted in an enriched list of 14 genes (with
variants) (COL4A2,COL6A3,COL6A6,ITGAX,LAMA5,ADAMTS9,CSGALNACT1,
TMOD2,HTR2B,RSC1A1,TRPV2,WNK1,ARSD and SPTBN5) involved in neural
functions. Additionally, a homozygous variant in NLRP11 gene and a
heterozygous variant in NAGPA gene were identified in STU-65 family that
needs further confirmation. Our results support the fact that stuttering
is a polygenic disorder. The putative gene targets identified in our
study can drive the research prospects to understand the underlying
mechanisms. We hypothesize multiple and combined mechanisms to be
involved in the genesis of stuttering. Keywords: Stuttering, exome
sequencing, neural pathways