RECURRENCE RISK OF MENTAL RETARDATION IN SIBS

Abstract

A survey of the recurrence risk rates in the sibs of 1,296 mentally retarded individuals is described. The figures were analysed on the basis of sex and degree of retardation. It was found that the sibs of moderately retarded males were significantly at risk. The recurrence risk rates in all other grades of retardation were higher than the random risk rate.