Gaucher's disease in South Africa.

The adult non-neuropathic form of Gaucher's disease has been identified in 32 patients in 25 Ashkenazi Jewish kindreds in South Africa. The minimum prevalence in this population is 1 in 5000, with a gene frequency of 0.014 and a carrier rate of 1 in 36. On correction for bias resulting from possible under-ascertainment, these minimum figures become 1 in 4000, 0.0166, and 1 in 30, respectively. Confirmation of autosomal recessive inheritance was obtained by segregation analysis by the 'a priori' and 'simple sib' methods. The Ashkenazin of South Africa have their origins in Lithuania and it is evident that the high gene frequency in South Africa is a reflection of the genetic constitution of the immigrant population. The localisation of the Gaucher gene to Lithuania represents a further step in the determination of the early geographic distribution of the genetic disorders of the Jewish race.