title: HLA class I and II polymorphisms in Azores show different settlements in Oriental and Central islands.
abstract: Human leucocyte antigen-A, -B, -Cw, -DRB1, -DQA1 and -DQB1 polymorphisms were examined in the Azorean population. The data were obtained at high-resolution level, using polymerase chain reaction (PCR) with sequence-specific primer, PCR-sequence-specific oligonucleotides and sequence-based typing. The most frequent allele in each locus was: A*0201 (24.5%), B*510101 (9.8%), Cw*0401 (14.8%), DRB1*070101 (18.3%), DQA1*0201 (17.4%) and DQB1*0301 (19.4%). The predominant extended haplotype was A*0202-B*1503-Cw*0202-DRB1*090102-DQA1*0303- DQB1*0202 (1.9%), which was found to be absent in the Portuguese mainland. The present study corroborates historical sources that say the Azores were populated not only by Portuguese but also by other Europeans, mostly Flemish people. Despite dendrogram analysis showing some remote Asian genetic affinities, the lack of specific alleles and haplotypes from those populations does not allow us to conclude for direct influence. Haplotype and allele frequencies in Azores show no homogeneous distribution between Oriental and Central islands of this archipelago. The Oriental islands harbour several haplotypes already found in mainland Portugal and identified as Mediterranean and European. The Central group of islands on the contrary clearly shows an influence of north Europeans (most probably derived from a well-documented Flemish settlement), with much less affinity to mainland Portugal.
authors.affiliation: Human Genetics Laboratory, University of Madeira, Funchal, Portugal.
authors.forename: H
authors.initials: H
authors.lastname: Spínola
authors.forename: A
authors.initials: A
authors.lastname: Brehm
authors.forename: B
authors.initials: B
authors.lastname: Bettencourt
authors.forename: D
authors.initials: D
authors.lastname: Middleton
authors.forename: J
authors.initials: J
authors.lastname: Bruges-Armas
mesh_terms: D000483:Alleles; D001208:Asia; D001394:Azores; D017931:DNA Primers / Q000737:chemistry; D005787:Gene Frequency; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D014644:Genetic Variation; D015234:HLA-A Antigens / Q000235:genetics; D015235:HLA-B Antigens / Q000235:genetics; D006683:HLA-DQ Antigens / Q000235:genetics; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; D006684:HLA-DR Antigens / Q000235:genetics; D059811:HLA-DRB1 Chains; D006239:Haplotypes; D006801:Humans; D015999:Multivariate Analysis; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012984:Software; D013223:Statistics as Topic
chemical_list: D017931:DNA Primers; D015234:HLA-A Antigens; D015235:HLA-B Antigens; D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; C069050:HLA-DQA1 antigen; C069051:HLA-DQB1 antigen; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains