Structural heterozygosis in man: analysis of two families

Summary Two families are described in each of which the father is presumed to have an autosomal reciprocal translocation as a result of which both children in one family, and one of three children in the other, are grossly abnormal. The reciprocal translocations are probably between chromosomes nos. 9 and 4 in the first family, and chromosomes nos. 1 and 6 in the second family. The abnormalities of karyotype in the children are regarded as examples of duplication deficiencies. Unusual dermal ridge patterns were observed in the individuals with abnormal karyotypes.