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Progressive hearing loss affects approximately 50% of the elderly by the age of 80, and is most likely caused by an interaction of genetic and environmental factors. Identification of the genes responsible for hereditary hearing loss is therefore important. Families with pure genetic degenerative hearing disorders may be helpful as the same genes may be also involved in age-related hearing Toss in general. In this study we have performed a genome search in an extended Dutch family with autosomal dominant progressive hearing loss starting in the high frequencies. The gene causing hearing loss in this family was localized to the short arm of chromosome 7, in a 15 cM interval between markers D7S493 and D7S632.

A histological review of 86 pediatric nephrectomy specimens from patients with vesicoureteric reflux (with or without apparent obstruction at the vesicoureteric junction) investigated the relationship between the presence and extent of focal and segmental glomerulosclerosis (FSGS) and coexisting renal hypoplasia and postnatally acquired cortical damage. FSGS was found in 18 patients, 9 of whom were less than 5 years old. There was no significant association between the presence (or grade) or absence of FSGS and age at nephrectomy, gender, presence or absence of obstruction, and severity of hypoplasia and/or postnatally acquired cortical loss. FSGS was absent from 18 hypoplastic kidneys without vesicoureteric reflux (although of relatively young age), 40 normally developed kidneys age-matched with the index population, and 72 nephrectomy specimens without vesicoureteric reflux (except in 2 known cases of focal segmental glomerulonephritis). Within the index population FSGS was significantly (P < .01) associated with hypertension, and hypertension was significantly associated with proteinuria (P < .001) but not with an abnormal contralateral kidney. There was no significant association between FSGS, proteinuria, and an abnormal contralateral kidney. Our results were unexpected when interpreted within a pathogenesis for FSGS of glomerular "hyperfiltration." They may, at least in the pediatric age group, indicate a possible role for other mechanisms in the development of FSGS.