AUTOSOMAL RECESSIVE NON-SYNDROMIC DEAFNESS LOCUS (DFNB8) MAPS ON CHROMOSOME 21Q22 IN A LARGE CONSANGUINEOUS KINDRED FROM PAKISTAN

Autosomal recessive childhood-onset non-syndromic deafness is one of t he most frequent forms of inherited hearing impairment. Recently five different chromosomal regions, 7q31, 11q13.5, 13q12, 14q and the peric entromeric region of chromosome 17, have been shown to harbour disease loci for this type of neurosensory deafness. We have studied a large family from Pakistan, containing several consanguineous marriages and segregating for a recessive non-syndromic childhood-onset deafness. Li nkage analysis mapped the disease locus (DFNB8) on the distal long arm of chromosome 21, most likely between D21S212 and D21S1225 with the h ighest led score of 7.31 at theta = 0.00 for D21S1575 on 21q22.3.