CONCLUSION
Decades of research has finally tied stuttering to certain genes and
changes in brain. Mutation screening of the three implicated genes
(GNPTAB , GNPTG and NAGPA) among 64 PWS,
resulted in a likely pathogenic allele frequency of 1.6%. Recurrence of
mutations in the three genes among our south Indian stuttering cohort
corroborates the causative of these genes to stuttering. Thus mutational
screening ended up with a minimal resolution of 3.1% (2/64) that could
be ascribed to these genes but remains inconclusive. Hence involvement
of more stuttering genes are predicted and can certainly be addressed
using next generation sequencing technology. Since stuttering is a
complex disorder two highly multiplex families were chosen from existing
database6 to identify new genes involved in related
pathways using exome sequencing in the second paper submitted in the
series.