Probable identification of an HL-A second-locus antigen associated with a high risk of nasopharyngeal carcinoma.

An HL-A antigen profile comprising an increased frequency of HL-A2 and undetectable second-locus antigen(s) in Chinese patients with nasopharyngeal carcinoma (N.P.C.) has been reported. To investigate whether the deficit of second-locus antigen(s) had a genetic basis, sera from parous women in Singapore were screened for anti HL-A activity corresponding to the second-locus "bland". A second-locus (Singapore-2) was identified which seems to be associated with a high risk of N.P.C.