An Erroneous Exclusion of Paternity in a Chinese Family Exhibiting the Rare MNSs Gene Complexes Mk and MsIII

. Because of an apparent exclusion of paternity of the type father M/child N, and of the father's insistent denial of this exclusion, a thorough investigation of the MNSs groups of a Chinese family was carried out. The ‘exclusion’ was proved false by the demonstration of Mk in the persons involved. It is the first time that this rare gene comes to notice through disputed paternity, and this is the first example of Mk in Chinese. The family also had several members possessing MsIII, a gene complex which produces M, s, and the antigens characteristic of Cell Class III in the Miltenberger sub-system. Three sibs of the propo situs had the very rare genotype MsIII/Mk. The medico-legal and serological aspects of the case adiscussed.