ABSTRACT
A Mexican population sample was obtained from the central region of the country, including five states. Two hundred and eleven individuals were PCR-typed for 15 STR loci with the AmpFiota STR Identifiler PCR amplification kit (Applied Biosystems). The following autosomal markers were analyzed: D8S1179, D21S11, D7S820, CSF1PO, D19S433, vWA, TPOX, D18S51, D3S1358, TH01, D13S317, D16S539, D2S1338, D5S818, FGA and Amelogenin. Allele frequencies for each STR were estimated and compared to previous reports. Genotype distribution by locus and by two loci combination was in agreement with Hardy-Weinberg expectations for all 15 STRs. This STR system in Mexican-mestizos presented a combined probability of exclusion (PE) and discrimination (PD) longer than 99.999%.
Subject(s)
Gene Frequency , Genetics, Population , Tandem Repeat Sequences , DNA Fingerprinting , Humans , Mexico , Polymerase Chain ReactionABSTRACT
In this review, we describe and discuss the genetic factors that, up to some point, determine resistance to the infection and control the progression of the disease in HIV-infected individuals. Genetic factors may account for non-progression or slow progression of the disease in some of so called long-term non progressors HIV-infected individuals. In general, this group shows no symptoms for more than 10 years, while their circulating T CD4+ cells levels remain stable and they usually have a low virus load. Even though non-progression and rapid progression phenomenon are still not fully understood, there probability exists that some class I and class II MHC alleles are associated with a greater or smaller risk to develop AIDS. Class I HLA-B*35 and Cw*04 alleles are the ones commonly associated with the rapid transition of the infection into AIDS. In contrast, heterozygosity for class I HLA alleles and, particularly, the absence of HLA-B*35 and Cw*04 may contribute to non-progression. Studies which set forward other HLA alleles as possibly taking part of the pathogenic mechanism of non-progression are also described; although, relevant methodological problems can be noticed. Furthermore, this review explains and discusses allelic variations for some of the components of the chemokine receptors family, particularly the genes which codify for CCR5 and CCR2 and other genetic factors such as the SDF1-3'. A variant of the alpha SDF1 chemokine gene that have been associated with AIDS' slow progression or non-progression in HIV-infected individuals. As a whole, the factors described in this review are those that influence the natural history of the disease due to HIV and give an example of what genetic or multigenetic influence can have over the pattern of evolution of HIV infection. Finally, we mention the possible implications that the identification of the genetic markers has in the pathogenesis of HIV disease and in the development of the new therapeutic strategies to control or eliminate HIV.
Subject(s)
Acquired Immunodeficiency Syndrome/genetics , HIV Infections/genetics , Acquired Immunodeficiency Syndrome/drug therapy , Acquired Immunodeficiency Syndrome/etiology , Cytokines/physiology , Disease Progression , HIV Infections/drug therapy , HIV Infections/etiology , Humans , Major Histocompatibility Complex/geneticsABSTRACT
The major histocompatibility complex (MHC) genes are highly polymorphic and therefore have been useful in population genetics and disease association studies. We analyzed restriction fragment length polymorphism of HSP70-2 alleles in healthy unrelated Mestizo, Mazatecan and Nahua populations. Both Indian groups, Mazatecans and Nahuas, were in Hardy-Weinberg equilibrium, while Mestizos were in disequilibrium (chi 2 = 0.399; P < 0.05). The Mazatecan Indians presented a high frequency of BB homozygosity (17.35%) compared to Mestizos (5%) (P = 0.01). Mexican ethnic groups present differences in distribution of BB genotype. The low frequency of BB genotype in Mestizos may be the result of a negative selection process.
