The Bubi population of Equatorial Guinea characterised by HUMTH01, HUMVWA31A, HUMCSF1PO, HUMTPOX, D3S1358, D8S1179, D18S51 and D19S253 STR polymorphisms

Admixture estimates for Churuguara, a Venezuelan town in the State of Falcón

BACKGROUND

The present Venezuelan population is the admixture product of Amerindians, Europeans and Africans, a process which was not homogeneous over the country. Blood groups, STRs and VNTRs, specifically D1S80, have been used successfully in admixture studies, but few have been made in Venezuela.

AIM

This study aims to estimate the admixture components of Churuguara, Venezuela, and to evaluate the genetic relationship of this population with other Venezuelan as well as worldwide populations through principal component analysis and the study of dendrograms based on genetic distances.

SUBJECTS AND METHODS

Gene frequencies of blood groups ABO and Rh (only anti D), of STRs VWA, F13A01, FES/FPS and VNTR D1S80 were studied in a sample of 60 individuals born in Churuguara, a Venezuelan town of admixed ancestry in the State of Falc6n. Admixture was estimated with Chakraborty's gene identity method, and Nei's standard genetic distance was used to build two dendrograms with the neighbour-joining approach, one based on the three STRs and the other based only on D1S80. Principal component analyses with the gene frequencies of these markers were also performed.

RESULTS

The frequency of allele ABO*O was 0.788, of ABO*A was 0.187 and of RH*D was 0.74. D1S80 showed 16 different alleles with a heterozygosity of 0.880, whilst the three STRs showed only eight different alleles and heterozygosities between 0.733 and 0.797. The estimates of admixture obtained in this analysis were 52.5% for the Spanish parental group, 27.6% for the African and 19.9% for the Amerindian. Comparison of Churuguara with other Latin American populations shows that its African component is not as high as that observed in Colombian Choco, but it is higher than that observed in other samples from Colombia, Chile and Maracaibo (Venezuela).

CONCLUSIONS

Results of the admixture analysis are consistent with those obtained with two dendrograms and principal component analyses, suggesting that the strong initial Amerindian component of 500 years ago has been diluted by the continuous flow of European genes, mainly Spanish, to this region.

Genetic structure of a Cuban population based on nine short tandem repeat loci

Cuba is a multiethnic and multiracial society. Here we describe the genetic variation of a sample of the Cuban population, which include the three most common racial groups, Caucasians, Negroids and Mestizos, by means of a set of nine microsatellites (HUMTH01, HUMTPOX, HUMCFS1PO, HUMVWA, HUMFESFPS, HUMF13A, HUMF13B, HUMLPL and HUMHPRTB). The analysis presented here indicates that these STR loci are highly informative for forensic purposes. The genetic data on the major racial groups is in good agreement with current demographic tendencies and with historic events that took place during the formation of the Cuban population.

The Fang population of Equatorial Guinea characterised by 15 STR-PCR polymorphisms

Allele frequencies for 15 STR loci (D8S1179, D21S11, D7S820, CSF1PO, D19S433, HUMVWA31A, HUMTPOX, D18S51, D3S1358, HUMTHO1, D13S317, D16S539, D2S1338, D5S818 and HUMFGA) were analysed in the Fang population of Bioko Island, Equatorial Guinea. No deviation from Hardy-Weinberg equilibrium was found for all loci. Statistical parameters demonstrated the forensic utility of the analysed systems.

17 STR data (AmpF/STR Identifiler and Powerplex 16 System) from Cabinda (Angola)

Allele frequencies for seventeen STRs included in the AmpF/STR Identifiler (CSF1PO, D2S1338, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D19S433, D21S11, FGA, TH01, TPOX, and VWA) and Powerplex 16 System (CSF1PO, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, FGA, Penta D, Penta E, TH01, TPOX, and VWA) were estimated from a sample of 110 unrelated individuals from Cabinda, Angola. Comparative analyses between our population data and other African databases, namely Promega's African-Americans, AB Applied Biosystems African-Americans and five other population samples gathered from the literature are also presented.

Variation at 16 STR loci in Rwandans (Hutu) and implications on profile frequency estimation in Bantu-speakers

A data set of 16 autosomal STRs (the 13 CODIS loci plus HumCD4, HumFES, HumF13A1) was obtained in a sample of 52 unrelated Hutus from Rwanda. Genotypes at all loci met Hardy-Weinberg expectations with the exception of HumCSF1PO. No significant evidence of association across alleles at independent loci was obtained. Statistical parameters demonstrated the forensic usefulness of the analysed systems (combined PE=0.9999996, combined PD=1:2.27 x 10(18)). Pairwise comparisons showed that the Hutu gene pool differs substantially from that of other Bantu-speaking populations suggesting the use of ethnic-specific population databases in forensic casework analysis. The introduction of a non-negligible bias was confirmed by calculating the differences between multiple-locus profile frequencies of western and eastern Bantoids using local and non-local reference databases.