The Rh_o Variant — D^u

Abstract

In a survey of 18,365 bloods for the incidence of the Du factor, in a population comprised approximately of 72 per cent Caucasoids, 15 per cent Negroids, 10 per cent Mexicans and 3 per cent Orientals, 78 Du bloods were found of which seven were type ccDuee. Of the latter, five came from Negroids and two from Caucasoids; the frequency among the two populations approximates respectively one in 6,000 and one in 500. In the general population of this region it is one in 2,500. The degree of reactivity of the type ccDuee found in this study was that of the “low grade” variety. However, from the remaining 71 “low grade” Du bloods, substantially weaker examples were found among type CcDuee and ccDuEe. The indirect antiglobulin and ficinized cell method readily detected type ccDuee; however, among the weaker variants, the antiglobulin method gave the more consistent results. It is concluded, therefore, that type ccDuee does occur in this area with a frequency that is considered significant and that its detection rests on the antiglobulin or other equally sensitive methods.

Rh(o) (D^u) Testing with Anti-Rh(o)' "(CDE) Reagents

“…In the population of the Baltimore-Washington area upon which we draw for blood donors we find the incidence of "low grade" 5îh0(ccDuee) to be 0.23 %, a six times greater incidence than in the Los Angeles area [1]. Since half of such variant bloods are agglutinated in a sfide test with anti-Rh0' "(CDE), the added use of the antiglobulin test would assist us in locating one 3?h0(Du) in a thousand donors.…”

“…Table I shows that some sera detected over half of the variant bloods and that some bloods were not agglutinated by any of the sera. Presumably the 56 % positive score we obtained with unselected com mercial anti-Rho' "(CDE) on the entire series of 88 bloods could be bettered by selecting sera as detailed in Table I and by using methods designed to increase the sensitivity of a particular serum [1].…”