LOCALIZATION OF A NOVEL GENE FOR NONSYNDROMIC HEARING-LOSS (DFNB17) TO CHROMOSOME REGION 7Q31

Autosomal recessive nonsyndromic hearing loss (ARNSHL) is the most com mon form of hereditary hearing impairment (HHI), To date, 16 different loci have been reported, making ARNSHL an extremely heterogeneous dis order. One of these loci, DFNB4, was mapped to a 5-cM interval of 7q31 in a large Middle-Eastern Druze family. This interval also includes t he gene for Pendred syndrome. We report on three new families with HHI from the Madras region of southern India that demonstrate linkage to 7q, Their pedigrees are compatible with autosomal recessive inheritanc e. Furthermore, the largest family identifies a novel locus (DFNB17) t elomeric to the DFNB4 and Pendred intervals, A 3-cM region of homozygo sity by descent between markers D7S486 and D7S2529 is present in all a ffected individuals in this family and generates a multipoint LOD scor e of 4.24. The two other families map to the previously reported DFNB4 region but have insufficient power to attain significant LOD scores, However, mutations in the Pendred syndrome gene are present in one of these families. Am. J, Med, Genet, 78:107-113, 1998, (C) 1998 Wiley-Li ss, Inc.