Relatedness among Basques, Portuguese, Spaniards, and Algerians studied by HLA allelic frequencies and haplotypes

 HLA-A, -B, -DRB1, -DQA1, and DQB1 alleles were studied in Iberian and Algerian populations by serology and DNA sequence methodologies. The genetic and cultural relatedness among Basques, Spaniards, and paleo-North Africans (Berbers or Tamazights) was established. Portuguese people have also maintained a certain degree of cultural and ethnic-specific characteristics since ancient times. The results of the present HLA study in Portuguese populations show that they have features in common with Basques and Spaniards from Madrid: a high frequency of the HLA-haplotypes A29-B44-DR7 (ancient western Europeans), A2-B7-DR15 (ancient Europeans and paleo-North Africans), and A1-B8-DR3 (Europeans) are found as common characteristics. Portuguese and Basques do not show the Mediterranean A33-B14-DR1 haplotype, suggesting a lower admixture with Mediterraneans; Spaniards and Algerians do have this haplotype in a relatively high frequency, indicating a more extensive Mediterranean genetic influence. The paleo-North African haplotype A30-B18-DR3 present in Basques, Algerians, and Spaniards is not found in Portuguese either. The Portuguese have a characteristic unique among world populations: a high frequency of HLA-A25-B18-DR15 and A26-B38-DR13, which may reflect a still detectable founder effect coming from ancient Portuguese, i.e., oestrimnios and conios; Basques and Algerians also show specific haplotypes, A11-B27-DR1 and A2-B35-DR11, respectively, probably showing a relatively lower degree of admixture. A neighbor-joining dendrogram place Basques, Portuguese, Spaniards, and Algerians closer to each other and more separated from other populations. Genetic, cultural, geological, and linguistic evidence also supports the hypothesis that people coming from a fertile Saharan area emigrated towards the north (southern Europe, Mesopotamia, the Mediterranean Islands, and the North African coast) when the climate changed drastically to hotter and drier ca 10 000 years B.C. Received: 18 April 1997 / 17 June 1997     

Linkage of GLO with HLA in a sample of the Spanish population

Summary GLO allele frequencies are studied in 100 unrelated normal Spaniards. GLO-S shows a frequency similar to that found in Caucasoids. Weak linkage disequilibria between some HLA-B and some HLA-DR antigens are described. DR3 and DR4 are GLO-F associated both in normal and insulin dependent diabetic Spaniards. GLO/HLA-DR loci distance is about 6cM according to our family studies; females show a higher GLO/HLA-DR recombination rate than males in our sample. NO GLO heterozygous excess or nul alleles are found.     

Morphological variability of the earlobe in a Spanish population sample

This article shows the morphological variability of the earlobe in a Spanish population of European origin. The frequencies of four lobe characteristics (attachment, contour, modeling, and size) and their degree of expression were studied. The relationship among the characteristics and the differences involving sex and laterality were also considered. The least frequent morphology, and of main use in solving forensic cases, was the very small size with triangle-pulled contour into the skin and crossed-discontinuous modeling. The most frequent morphology, and most clinically useful, was the medium-sized lobe with free-arched contour and eminent or cross-continuous modeling. The characteristics were all symmetric. Size and modeling showed sexual dimorphism. Some characteristics were associated with each other: attachment with contour and modeling and the contour with modeling and size. The least frequent peculiarities were sharp lobe and virgule. The literature is scarce on this matter, practically non-existent for some characteristics, especially modeling and peculiarities. For the first time, the associations of the ear characteristics were analyzed, and this information could be applied to forensic identification.     

C3 polymorphism,HLA and chronic renal failure in Spaniards

Summary C3 allele frequencies were studied in 196 unrelated normal Spaniards. The results fit the Hardy-Weinberg equilibrium. No rare variants were detected. The C3 frequency was close but slightly higher than that found in other Caucasoid populations, and higher than that found in Negroids and Orientals. Spanish Basques also showed a high C3^F frequency. A North-South decreasing C3^F gradient was recorded and compared to other gradients (HLA-D/DR, height, etc.) thought to be due to natural selection. Lod scores in 28 Spanish families excluded C3 gene assignment at less than 45cM of HLA/GLO linkage group; no significant linkage disequilibrium was found between C3 and HLA. C3^F was also significantly increased in 20 chronic renal failure (CRF) patients as compared to 196 controls; this would support the existence of functional differences between C3^F and C3^S alleles.     

Are the Basques a single and a unique population?

Different analyses of genetic polymorphisms performed on the Basque population have suggested a possible heterogeneity of the Basques and a singularity of their genetic characteristics. In this paper, both aspects are analyzed by means of the genetic study of seven polymorphic systems--ACP, ADA, AK, ESD, PGD, GC, and HP--in 854 autochthonous individuals from the province of Vizcaya. The individuals were classified as being from the regions of Arratia, Guernica, Durango, Uribe, Marquina, Lea, and Bilbao, on the basis of the birthplaces of their four grandparents. Analyses for heterogeneity of the gene frequencies distribution suggest that there is a moderate genetic heterogeneity, probably produced by centuries of geographical and administrative isolation of these regions. The comparison with caucasoid populations, performed using the principal components analysis and Cavalli-Sforza and Edwards arc distance, indicates that the subpopulations of the province of Vizcaya have experienced little genetic exchange with other caucasoids and that the distribution of their genetic frequencies differentiates them from other populations.     

Frequency of HLA alleles in a sample population from Campania

The authors present their findings on the HLA A and B antigens frequent in Campania by means of a 127 random people sample. Only the HLA 1-8 aplotype shows a clear crossing-over disequilibrium.     

Association of HLA class I antigens and HLA class II alleles with vitiligo in a Turkish population

As is the case with many other autoimmune diseases, there is an association between vitiligo and HLA complex. HLA subtypes vary with racial/ethnic background. The purpose of this study was to determine which HLA class I antigens and HLA class II alleles are associated with Turkish vitiligo patients. Forty-one patients with vitiligo and 61 healthy control subjects were typed for HLA class II alleles. Thirty-three out of 41 patients with vitiligo and 100 healthy transplant donors were typed for HLA class I antigens. HLA DNA typing was performed by polymerase chain reaction/sequence specific primer method for class II. HLA typing for class I was performed by serological method. The frequency of HLA DRB1*03 was 0.6340 in patients compared to 0.2950 in controls (P = 0.0014). The frequency of HLA DRB1*04 was found to be 0.6830 in patients compared to 0.2950 in controls (P = 0.00026). The allele HLA DRB1*07 was present in 0.390 of patients compared to 0.0820 of the controls (P = 0.0004). A preventive antigen for the manifestation of vitiligo has not been identified in this study. Our findings suggest that DRB1*03, DRB1*04 and DRB1*07 alleles are genetic markers for general susceptibility to vitiligo in a Turkish population.     

Distribution of HLA A,B and C antigens in an Australian population

Summary HLA A and B antigens have been determined in 2740 adult responders to a population health survey in Busselton, Western Australia. HLA A B and C antigens have been determined in 481 schoolchildren. The antigen frequencies are generally close to those obtained elsewhere for subjects of British origin, but there are some differences from the frequencies found in North American Caucasians. The frequencies were not affected by the inclusion of genetically related individuals in the sample. Seventeen HLA A-B haplotypes, six A-C haplotypes and six B-C haplotypes had frequencies above 1%. A total of 1071 distinct phenotypes were identified out of the 5069 which are theoretically possible for the HLAA-B model used in the study. The most frequent phenotype was A2, B12 which occurred in 2.5% of the sample.     

Distribution of HLA antigens in the armenian population of Nagornyi Karabakh

Characteristics of the distribution of 31 HLA antigens of classes I (A, B, and Cw) and II (DR) in Nagornyi Karabakh Armenians are reported for the first time. It has been found that the antigens most common in this population are A2, A3, A9, B5, B7, B12, Cw4, DR4, DR2, and DR3; the least common antigens are B15, B16, and B40. The results are compared with the data for Armenians living in Armenia and those for major ethnic groups. The frequencies of HLA antigens in Nagornyi Karabakh Armenians match those in Armenians living in Armenia. In the HLA-antigen distribution, Armenians are generally close to Caucasoids.     

The HLA system of the Uzbek population in the Ferghana Valley. HLA antigens, genes and haplotypes of the Uzbek population in relation to its ethnogenesis

Pecularities of distribution of 40 HLA antigens within the Uzbek population of the Ferghana Valley have been studied. The frequencies of these antigens are subdivided into three main groups having frequencies characteristic of the following populations: Caucasoid population (A9, B40, Bw22 etc.); Mongoloid population (B8, B7, B12); Middle Asian population (Aw31, B13, B16, Bw35), probably. The Uzbek population contains haplotypes both of Europeoid (Aw30, B13; A3, Bw35) and Mongoloid origin (A9, B40) and, probably, of the local origin (A1, B14; A1, Bw53; Aw32, B40). The data on the HLA genetics of the Uzbeks confirm the historical, linguistic and anthropological information concerning the role of inhabitants of the Central Asia in ethnogenesis and formation of the modern Uzbek population.     

The Basques: review of population genetics and Mendelian disorders

The Basques live at the western end of the Pyrenees along the Atlantic Ocean and are thought to represent the descendants of a pre-Neolithic people. They demonstrate marked specificities regarding language and genetics among the European populations. We review the published data on the population genetics and Mendelian disorders of the Basques. An atypical distribution in some blood group polymorphisms (ABO, Rhesus, and Duffy) was first found in this population. Subsequently, additional characteristics have been described with regard to proteins (enzymes and immunoglobulins) and the HLA system. The advent of molecular biology methods in the 1990s allowed further insights into Basque population genetics based mainly on Y-chromosome and mitochondrial DNA. In addition, the Basques demonstrate peculiarities regarding the distribution of various inherited diseases (i.e., unusual frequencies or founding effects). Taken together, these data support the idea of an ancient and still relatively unmixed population subjected to genetic drift.     

Serologic polymorphism of the HLA Class 2 antigens in the Russian population]

Two hundred and thirty Russian Moscovities (108 healthy individuals and 122 cadaver kidney donors) were typed for antigens HLA-DR1-DRw10, HLA-DRw52-DRw53, and HLA-DQw1 and DQw3. HLA-DR1, 2, 3, 4, 5 and 7 were investigated in all individuals, the other having been only studied in portions of the material. The HLA class 2 antigens' polymorphism in Russian population has been shown to have features common to all Caucasians. Most widely distributed antigen is DR2 (phenotype frequency is 36%). Antigens DRw8, DR9 and DRw10 are rare. DR allele distribution demonstrated perfect fits to Hardy--Weinberg expectations. Antigens DR5 and DR4 are considered most difficult to define at early stage of the study.     

HLA class II antigens positively and negatively associated with hepatosplenic schistosomiasis in a Chinese population

To identify possible associations between host genetic factors and the onset of liver fibrosis following Schistosoma japonicum infection, the major histocompatibility class II alleles of 84 individuals living on an island (Jishan) endemic for schistosomiasis japonica in the Poyang Lake Region of Southern China were determined. Forty patients exhibiting advanced schistosomiasis, characterised by extensive liver fibrosis, and 44 age and sex-matched control subjects were assessed for the class II haplotypes HLA-DRB1 and HLA-DQB1. Two HLA-DRB1 alleles, HLA-DRB1*0901 (P=0.012) and *1302 (P=0.039), and two HLA-DQB1 alleles, HLA-DQB1*0303 (P=0.012) and *0609 (P=0.037), were found to be significantly associated with susceptibility to fibrosis. These associated DRB1 and DQB1 alleles are in very strong linkage disequilibrium, with DRB1*0901-DQB1*0303 and DRB1*1302-DQB1*0609 found as common haplotypes in this population. In contrast, the alleles HLA-DRB1*1501 (P=0.025) and HLA-DQB1*0601 (P=0.022) were found to be associated with resistance to hepatosplenic disease. Moreover, the alleles DQB1*0303 and DRB1*0901 did not increase susceptibility in the presence of DQB1*0601, indicating that DQB1*0601 is dominant over DQB1*0303 and DRB1*0901. The study has thus identified both positive and negative associations between HLA class II alleles and the risk of individuals developing moderate to severe liver fibrosis following schistosome infection.     

Immunofixation for C2 typing: C2 allotypes in Spaniards in relation to HLA,Bf and C4

Summary C2 typing is performed by immunofixation with anti-C2 antiserum instead of by a hemolytic overlay. This method gives sharp band definition, is less cumbersome than the hemolytic overlay, gel files are easily made, and it also enables one to describe putative new nonhemolytic variants. C2 allele frequencies were studied in a sample of the normal Spanish population and were found to be similar to other Caucasoids. HLA-Bw62,-Cw3, and-DR4 were significantly associated with C2 B. Concordantly, the only C2^*B extended HLA haplotype found in family material was Bw62-Cw3-Bw6-(DR4)-Bf^*S-C2^*B-C4A^*3 B^*2-(GLO^*1). C4A^*4 B^*2 and C4A^*4 B^*4 are not found within the same haplotype together with C2^*B and Bw62 or Bw22 respectively, nor do other C2^*B haplotypes occur with common HLA-B alleles. These results may favour the hypothesis that the Bw62-C2^*B haplotype is produced by one mutation arising in the Bw62-C2^*C haplotype and that subsequent crossovers can explain other C2^*B haplotypes (including Bw22-C2^*B).     

HLA antigens among Chinese in Taiwan: association of Cw1 and Cw3 on the same haplotype

HLA-A, B and C phenotypes and gene frequencies of Chinese living in Taiwan are presented. Cw1 and Cw3 were frequently found to segregate together on the same haplotype.