Abstract: A survey on 11 red cell blood groups of Hui ethnic group in Ningxia was reported A total number of 208 unselected samples was examined with twenty anti-sera, namely, anti-A -B, -M, -N, -S, -s, -D, -C, -e, -E, -P1, -Lea, -Leb, -Fya, -Fyb, -Jka, -Dia, -K, -Lua and -Xga.
A high frequency of B phenotype. (81. 91%) was found. Gene frequencies of r, p and q were 0. 5239, 0. 2231 and 0. 2530, respectively. The ABO blood groups distribution of Hui in the present study was similar to that of the previous report.
It was the first time for Hui ethnic group to be tested with anti-M, -N, -S and -s simultaneously. A low rate of S gene was found. The s frequency of Hui was significantly lower than that of Uygur in Xinjiang and Tibetan ethnic groups, and close to that of Mongolian, but was higher than that of Han, Korean, Zhuang, Dong and Gaoshan ethnie groups. The frequencies of chromosome MS, Ms, NS and Ns were 0. 0281, 0. 4422, 0. 0313 and 0. 4984, respectively.
Only one sample of Rh (D-) was observed with d gene frequency being 0. 0557. Of 179 people tested only 44 or 24. 58 per cent were positive with anti-P1. The calculated gene P1 frequency was 0. 1316. This result was significantly lower than that of previous study.
In Lewis group, there. was a high frequency of Le (a-b-) (17. 81%) . No one Le (a+b+) phenotype was found. The Le" gene frequency was 0. 3882.
Only two Fy (a-b+) cases were obtained in 219 tested the Duffy blood group. The high Fy' gene frequency (0. 9270) in Hui ethnie group was similar to that of other ethnic groups of China.
Only anti-Jka serum were employed to test the Hui ethnic group. 151 samples among 219 tested were Jk (a+) . The Jke gene frequency was 0. 4428.
In the Hui ethnic group, 15 samples (6. 85%) were found to be Di"-positive and the Dia gene frequency in Hui ethnic group was 0. 0349.
All people were negative with anti-K and -Lua sera.
Of 219 samples tested only 5 people were female. In Xg blood group, one female and 98 males were found to be of Xg (a+) phenotype. TheXga gene frequency in Hui ethnic group appeared to be 0. 4432.
The genetie distances between 6 populations were computed by Nei's method (1978) and a phylogenetic tree of these populations was constructed on the basis of genetie distances caleulated with data of gene or chromosome frequencies of 11 red cell hlood groups, namely, ABO, MNSs, Rhesus, P, Lewis, Duffy, Kidd, Kell, Diego, Lutheran and Xg. The result of the genetie distances showed that the Hui ethnic group was gemetically close to Han and other ethnic groups of North China and far from Uygur ethnie group of Northwest China.

Key words: Human population genetics; Hui ethnic group; Blood group; Gene frequency; Genetic distance