Physical Anthropologic And Population Genetic Characteristics Of Mulao Minority In Guangxi Province

Objectives:To investigate the physical characteristics,somatotype and genetic polymorphism in 15 STRs of Mulao minority in Guangxi province,and to provide the important clues to probe into the origin of Mulao minority,as well as the genetic relationships between Mulao and other nationalities in China.Methods:The healthy Mulao adults from 6 remote villages of Guangxi province was randomly selected as study groups that strickly meet the age requirement of 20 to 60 years old and whose parents are teal Mulao nationalities. 44 items of anthropometry(17 items of head and face,and 27 items of body) from total 410 individuals(167 males,and 243 females),were investigated.The physical anthropometry was performed by WU Ru-Kang's methods,and the somatotype measurements were evaluated by Heath-Carter methods.Meanwhile, whole blood samples were obtained from 183 unrelated Mulao individuals by venipuncture,and then DNA was extracted with the method of Chelex 100.15 STR loci were co-amplified using AmpFeSTR(?)Identifiler^TMPCR Amplification kit,and electrophoresis and detection of PCR products were carried out with the ABI Prism 3100 Genetic Analyzer.Results:(1)Physical characteristics of Mulao were as follows: sub-medium and short stature(the average stature is 1617.24mm for male and 1508.69mm for female),among which thin and tall type and long length of trunk were for male,while medium type and medium length of trunk for female.The highest percentage of measurements for mesocephaly,hypsicephaly,acrocephaly hyperleptoprosopy,leptorrhiny and mesorrhiny,medium chest circumference, mesatiskelic type,broad breadth of shoulder,and hyperwide hand were distributed in both male and female.The results show that Mulao has the characteristics of both southern nationalities in China and them.Physical comparisons made between male and female found that both sexes shared similar features in head and face,while significant differences existed in the rest body features.(2)Variational curves of physical characteristics:In all the 4 groups,mean stature of male and female decreased with age,body weights varied from 20 to 49 years old,then reduced significantly after the age of 50. Mean value of horizontal head circumference changed slightly,while circumference of trunk and limps varied significantly,which were highest in middle age except for that of thigh and leg.The maximum value of skinfolds of trunk was also observed in middle age,while that of limps in young age.In addition,each skinfold of female was thicker than that of male counterpart in the same-age group.(3)The results of cluster of physical characteristics among Mulao and other nationalities found that 26 populations in both sexes were split into southern and northern groups,respectively.Mulao was clustered into the southern groups and close to Gelao and Achang nationalities.(4)The mean somatotype of male is a balanced Mesomorph category,while that of female is Endo-Mesomorph,which belongs to the somatotype of southern nationalities.(5) The comparison results of somatotype between Mulao and other nationalities were as follows:The results of SAD showed that the mean somatotype in both sexes is closer to Hui's and Dong's.The results of cluster analysis showed 14 male and female populations were split into southern and northern groups, respectively.Mulao was clustered into the southern groups and close to Hui and Dong.(6)Genetic structure of Mulao were as follows:135 alleles and 424 genotypes for 15 STR loci were observed in Mulao,with frequencies ranging from 0.0027～0.5301 and 0.005～0.339,respectively.The most frequent allele and genotypes were TPOX^*A8 and TPOX*A8/A11,respectively. D8S1179^*A11 was the specific allele with high frequency only observed in Mulao.The average H＞0.7,DP＞0.8,EPP＞0.5,PIC＞0.5;the cumulative DP,EPP, and PIC are above 0.999999.(7)The genetic relationships among Mulao and other nationalities:Cluster analyses of 35 populations show that they were split into three groups—southern,northern and southern-northern groups, respectively.Mulao was clustered into the southern group and close to Dong, Maonan,Zhuang,and Han nationalities in Guangxi province.The results of genetic relationships between Mulao and other nationalities in Guangxi were as follows:Mulao possessed closer genetic distances from Miao,Han,and Dong; while far distances from Yi and Shui.Analyses of cluster,phylogenetic tree and principal-components found that 10 nationalities were split into three groups—Yi and Shui formed one group by itself,respectively,while Mulao together with the rest nationalities formed another group and had a close linkage with Dong,Maonan,Zhuang,et al.Conclusions:(1)The above data of physical anthropometry and 15 STRs loci in Mulao population can provide information for anthropologic and population genetic researches.(2)The combination analyses of physical characteristics,somatotype and STR show that Mulao belongs to typical southern nationality.The physical characteristics of Mulao had a tendence to similar to southern Asian of Mongoloid.Because gene cluster,phylogenetic tree and principal-components analyses show that Mulao was closer to Dong, Maonan and Zhuang nationalities,and combinded analyses of the record of historical materials,Mulao possibly descend from the same origination of southern ancient Baiyue minority as above nationalities.(3)Analyses of STR in nationalities can provide more reliable genetic relationships compared with those of physical characteristics and somatotype.(4)The data provided from above 15 STRs loci,except for TPOX and TH01,are useful in forensic individual identification,paternity investigation,and human population genetic research.