GJB2 and deafness: Among the 38 infants who failed the NHS, 9 (24%) segregated for 2 mutated GJB2 alleles (including 8 p.V37I homozygotes and 1 p.V37I/c.235delC compound heterozygote), 9 (24%) segregated for 1 mutated GJB2 allele (including 8 p.V37I heterozygotes and 1 c.235delC heterozygote), and 20 (53%) segregated for none of the 4 deafness-associated mutations (Table 4).