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In undertaking a study of the history of the dogmatic trajectory in the Catholic Church, the importance of the role of the "sense of the faith" (sensus fidei) of the Christian people can be observed as a factor in its progress and evolution. Through this supernatural instinct, enlightened by the Holy Spirit, all the people people of God receive the gift of discerning the truths of faith that are virtually contained in the Divine Revelation. This sense of faith of the faithful has always had a particu-larly special connection with the figure of Mary, the Mother of Jesus. The dogmatic proclamation of both the Immaculate Conception and the Assumption into Heaven constitutes a paradigmatic instance of this interrelationship. [ABSTRACT FROM AUTHOR]

Background: The apolipoprotein E ( APOE) gene plays a pivotal role in cholesterol metabolism. Since the discovery of the APOE*2 and APOE*4 as the major susceptibility alleles for several diseases including dyslipidemia, atherosclerosis, coronary heart disease, late-onset and early Alzheimer's disease, the APOE genotype might be considered as a potential predictive factor for both epidemiological research and diagnosis. Aim: The aim of this study is to report on the polymorphism of the APOE gene in the 'Paisa' population from northwest Colombia (Antioquia) to obtain a population baseline of the existing variation in this locus. Method: One thousand and one healthy voluntaries were genotyped for the APOE polymorphism using polymerase chain reaction-restriction fragment length polymorphism technique. Results: The APOE*3/*3 genotype presented the highest frequency (66.33%) and the APOE*4/*4 had the lowest frequency (1.89%). Genotype frequencies comply with Hardy-Weinberg expectations. Allele frequencies obtained for APOE*2, APOE*3 and APOE*4 were 0.075 ± 0.005 (95% CI = 0.063-0.086), 0.814 ± 0.009 (0.797-0.831) and 0.111 ± 0.007 (0.098-0.125), respectively. Conclusion: Although globally the high-to-low APOE frequency follows the E*3 > E*4 > E*2 trend, the present APOE frequency data is in disagreement with some reports from South-American countries. [ABSTRACT FROM AUTHOR]

The main genetic factor related to HIV-1 resistance is the CCR5-Δ32 mutation; however, the homozygous genotype is uncommon. The CCR5-Δ32 mutation along with single nucleotide polymorphisms (SNPs) in the CCR5 promoter and the CCR2-V64I mutation have been included in seven human haplogroups (HH) previously associated with resistance/susceptibility to HIV-1 infection and different rates of AIDS progression. Here, we determined the association of the CCR5 promoter SNPs, the CCR5-Δ32 mutation, CCR2-V64I SNP, and HH frequencies with resistance/susceptibility to HIV-1 infection in a cohort of HIV-1-serodiscordant couples from Colombia. Seventy HIV-1-exposed, but seronegative (HESN) individuals, 57 seropositives (SP), and 112 healthy controls (HC) were included. The CCR5-Δ32 mutation and CCR2-V64I SNP were identified by PCR, and the CCR5 promoter SNPs were evaluated by sequencing. None of the individuals exhibited a homozygous Δ32 genotype; the CCR2-I allele was more frequent in HESN (34%) than HC (23%) ( p=0.039, OR=1.672). The frequency of the 29G allele was higher in SP than HC ( p=0.003, OR=3). HHF2 showed a higher frequency in HC (19%) than SP (9%) ( p=0.027), while HHG1 was more frequent in SP (11.1%) than in HC (4.2%) ( p=0.019). The AGACCAC- CCR2-I-CCR5 wild-type haplotype showed a higher frequency in SP (14.2%) than in HC (3.7%) ( p=0.001). In conclusion, the CCR5- Δ32 allele is not responsible for HIV-1 resistance in this HESN group; however, the CCR2-I allele could be protective, while the 29G allele might increase the likelihood of acquiring HIV-1 infection. HHG1 and the AGACCAC- CCR2-I-CCR5 wild-type haplotype might promote HIV-1 infection while HHF2 might be related to resistance. However, additional studies are required to evaluate the implications of these findings. [ABSTRACT FROM AUTHOR]

We report an integrated analysis of nuclear (autosomal, X- and Y-chromosome) short tandem repeat (STR) data and mtDNA D-loop sequences obtained in the same set of 22 Native populations from across the Americas. A north to south gradient of decreasing population diversity was observed, in agreement with a settlement of the Americas from the extreme northwest of the continent. This correlation is stronger with 'least cost distances,' which consider the coasts as facilitators of migration. Continent-wide estimates of population structure are highest for the Y-chromosome and lowest for the autosomes, consistent with the effective size of the different marker systems examined. Population differentiation is highest in East South America and lowest in Meso America and the Andean region. Regional analyses suggest a deviation from mutation-drift equilibrium consistent with population expansion in Meso America and the Andes and population contraction in Northwest and East South America. These data hint at an early divergence of Andean and non-Andean South Americans and at a contrasting demographic history for populations from these regions. [ABSTRACT FROM AUTHOR]

Lutzomyia evansi (Núñez-Tovar) is the vector of the parasite Leishmania infanfum in rural zones of Northern Colombia. An attempt was made to determine the origin of a recently detected urban population of Lutzomyia evansi by genetically characterizing specimens from seven geographically distinct localities in the Colombian Caribbean. Insect specimens were collected in rural and urban environments of areas endemic for visceral leishmaniasis or free of the disease. Nine polymorphic sites, nine nucleotide haplotypes and a single aminoacid haplotype were found within the 315 bp fragment sequenced, corresponding to the 3' end of the cytochrome b mitochondrial gene. Paired genetic distances between the haplotypes, estimated with the Kimura two-parameters model, varied from 0,0032-0,0194. Analysis revealed low genetic variability between specimens from urban and rural localities. Several of the sand flies collected in the city of Sincelejo (department of Sucre), where autochthonous visceral leishmaniasis cases have appeared in recent years, were genetically similar to those of a rural focus of the disease (El Contento, on the neighboring department of Córdoba). The epidemiological implications of this finding for Leishmania infanfum transmission in the Colombian Caribbean are discussed. [ABSTRACT FROM AUTHOR]

The large and diverse population of Latin America is potentially a powerful resource for elucidating the genetic basis of complex traits through admixture mapping. However, no genome-wide characterization of admixture across Latin America has yet been attempted. Here, we report an analysis of admixture in thirteen Mestizo populations (i.e. in regions of mainly European and Native settlement) from seven countries in Latin America based on data for 678 autosomal and 29 Xchromosome microsatellites. We found extensive variation in Native American and European ancestry (and generally low levels of African ancestry) among populations and individuals, and evidence that admixture across Latin America has often involved predominantly European men and both Native and African women. An admixture analysis allowing for Native American population subdivision revealed a differentiation of the Native American ancestry amongst Mestizos. This observation is consistent with the genetic structure of pre-Columbian populations and with admixture having involved Natives from the area where the Mestizo examined are located. Our findings agree with available information on the demographic history of Latin America and have a number of implications for the design of association studies in population from the region. [ABSTRACT FROM AUTHOR]

We examined genetic diversity and population structure in the American landmass using 678 autosomal microsatellite markers genotyped in 422 individuals representing 24 Native American populations sampled from North, Central, and South America. These data were analyzed jointly with similar data available in 54 other indigenous populations worldwide, including an additional five Native American groups. The Native American populations have lower genetic diversity and greater differentiation than populations from other continental regions. We observe gradients both of decreasing genetic diversity as a function of geographic distance from the Bering Strait and of decreasing genetic similarity to Siberians--signals of the southward dispersal of human populations from the northwestern tip of the Americas. We also observe evidence of: (1) a higher level of diversity and lower level of population structure in western South America compared to eastern South America, (2) a relative lack of differentiation between Mesoamerican and Andean populations, (3) a scenario in which coastal routes were easier for migrating peoples to traverse in comparison with inland routes, and (4) a partial agreement on a local scale between genetic similarity and the linguistic classification of populations. These findings offer new insights into the process of population dispersal and differentiation during the peopling of the Americas. [ABSTRACT FROM AUTHOR]

The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved1–5. One contentious issue is whether the settlement occurred via a single6–8 or multiple streams of migration from Siberia9–15. The pattern of dispersals within the Americas is also poorly understood. To address these questions at higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. We show that Native Americans descend from at least three streams of Asian gene flow. Most descend entirely from a single ancestral population that we call “First American”. However, speakers of Eskimo-Aleut languages from the Arctic inherit almost half their ancestry from a second stream of Asian gene flow, and the Na-Dene-speaking Chipewyan from Canada inherit roughly one-tenth of their ancestry from a third stream. We show that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America. A major exception is in Chibchan-speakers on both sides of the Panama Isthmus, who have ancestry from both North and South America.

A correction to the article "Reconstructing Native American population history" that was published in the 2012 issue is presented.

Introduction: Aedes aegypti populations may experience changes in abundance and genetic diversity in addition to changes in their evolutionary capability to respond to vector control. The knowledge on the changes in genetic variation on a spatio-temporal scale improves the epidemiological understanding of dengue and supports the appropriate and timely design of vector control strategies., Objective: To assess the genetic changes, diversity and gene flow in six microgeographical populations of Ae. aegypti in Medellín for different epidemiological periods of dengue., Materials and Methods: A total of 255 specimens from six different neighborhoods in Medellín were used to assess variations in the CO1 mtDNA haplotype composition, diversity and genetic differentiation for an epidemic period (2010) and an endemic period (2012)., Results: Two groups of highly differentiated haplotypes were present in both periods, and a high-frequency haplotype was assessed for all neighborhoods. The highest haplotype diversity was recorded in 2012, but the maximum nucleotide diversity was recorded in 2010. No significant correlation between genetic and geographic distances was observed., Conclusions: The genetic composition of Ae. aegypti varies over time without a predictable pattern. In addition, the presence of a high-frequency haplotype in both periods could indicate a persistent variation adapted to vector control. However, the simultaneous movement of highly differentiated CO1 haplotypes compatible with multiple introductions suggests that different gene pools would be suitable for transmission. These results are consistent with mosquito dispersion due to human activities, which would enable the rapid spread of the virus during epidemics in Medellin.

Introduction: Polymorphisms in promoters of genes code for cytokines that affect transcription levels. Several have been associated with leprosy patients that have functional and clinical implications., Objective: Polymorphisms in the promoter of the IL10 gene of leprosy patients will be compared frequencies in normal population., Materials and Methods: SNPs (single nucleotide polymorphism) -1082 A/G (rs1800896), -819C/T (rs1800871), and -592A/C (rs1800872) were identified in 100 leprosy patients and in a control group of 100 volunteers from a leprosy endemic region of Colombia., Results: The genotypes C/C and C/T in the SNP -819 were associated together with leprosy (OR=4.34, p<0.001).Similarly, the genotypes C/C and C/A in the -592 SNP showed an association (OR=4.3, p<0.001). The haplotypes -819C-519C and -1082A-819C-592C showed significant association (OR=4.34, p<0.001 and OR=6.25, p<0.001) respectively. These haplotypes in homozygosis conditions were also associated with leprosy: -819C-519C/-819C-519C (OR=4.34, p<0.001), -1082A -819C-592C/-1082A -819C-592C (OR=1.90, p=0.04). The SNP -1082 was not associated with leprosy in this population., Conclusions: The haplotypes associated with leprosy, -1082A-819C-592C/-1082A-819C-592C, have been reported as low producers of IL-10. Functionally, the low production of IL-10 may have immune response consequences and clinical implications. Additional haplotypes of IL-10 have been reported as markers for leprosy susceptibility or resistance in other ethnic populations. This suggests that differences in distribution of diverse IL-10 gene polymorphisms among ethnic groups may indicate important gene-disease associations.

Introduction: Genetic studies of Trypanosoma cruzi have tried to establish relations between genetic variants and their biological characteristics, such as clinical manifestations, host or geographic origin. However, much controversy exists on the associations between the commonly used DNA markers with group, clinical characteristics and disease epidemiology., Objective: In this study determined the variability of the genes that code for the proteins trypanothione reductase and cruzipain, both involved in the infection and survival of the parasite in the mammalian host, was studied and the association between genetic polymorphism and biological and geographic sources in Colombian T. cruzi strains was examined., Materials and Methods: The genotypes for each of six SNPs (single nucleotide polymorphisms) for trypanothione reductase and eight SNPs for cruzipain genes were identified by polymerase chain reaction-restriction fragment length polymorphism in 36 T. cruzi Colombian stocks from several regions and biological origins., Results: Three genotypes were identified for trypanothione reductase with Acy I and Hae III enzymes and six genotypes for cruzipain with the Rsa I, Ban I and Bsu 361 enzymes., Conclusions: For trypanothione reductase, an association was not established with biological or geographical origin; however, alleles at positions 102 and 210 allowed discrimination with groups I and II. For cruzipain, specific genotypes were associated with group, biological and geographic origin. The usefulness of molecular markers on these genes was demonstrated for the determination and differentiation of genetic varieties in T. cruzi.

Introduction: Surname frequency (isonymy) is used as a marker of paternal lineage and is used to characterize human population structure. Principles of isonymy were used to determine the genetic structure, migration rates, ancestry relations and origins of populations. This analysis was applied to two historically related local populations which currently are considered to be genetically isolated., Objective: The genetic relationships and influence zones of the Aranzazu and Marinilla populations were assessed by means of surname frequency analysis., Materials and Methods: Data originated from database with the title "System of Identification of Beneficiaries of the Social Programs" database or Sisben. Population parameters such as a priori kinship (phi(ii)), population homogeneity with B and C estimators, and Cavalli-Sforza's genetic distance were calculated for (a) three towns of Marinilla and its influence zone and (b) Aranzazu. The Rionegro population served as an external, comparison population., Results: The Aranzazu and Marinilla populations showed the higher homogeneity (B value between 0.25 and 0.5) in contrast with Rionegro (B = 0.159), as well as greater a priori kinship values (4), between 0.003 and 0.010). The lowest distances were found between Marinilla and Aranzazu., Conclusions: Aranzazu is a population with characteristics similar to those of Marinilla and its influence zone. The close similarity of genetic characteristics for these populations is due probably to a founder effect. Furthermore, the genetic similarity predicts that genetic diseases will have the same etiology in both populations and provides optimum conditions for gene mapping studies.

The verrucarum group of phlebotomine sand flies includes vectors of Leishmania spp. and Bartonella bacilliformis, and from the perspective of public health is considered as one of the most important groups of neotropical phlebotomine sand flies. Due to marked morphological similarity among species constituting this group, the identification based on conventional taxonomic characters can be difficult. Consequently, the verrucarum group has been the focus of numerous taxonomic comparisons which have included the following methods: chaetotaxy, morphometry, larval spiracular system, chorionic structure, morphology of the genital atrium, cytogenetics, morphological phylogenetics, isoenzymes, random amplified polymorphic DNA, cuticular hydrocarbons, DNA probes, and nuclear and mitochondrial nucleotide sequences. Based on morphological characters of the male terminalia, the verrucarum group has been divided in four series, i.e., verrucarum, serrana, townsendi and pia. Since the revision of the group made by Young and Duncan in 1994, ten new species, principally of Andean origin, have been assigned to 3 of the series verrucarum (L. maranonensis, L. cajamarcensis, L. antioquiensis, L. falcaorum), serrana (L. robusta, L. guilvardae) and pia (L. suapiensis, L. tihuiliensis, L. tocaniensis, L. limafalcaoae). The total number of verrucarum group members is now 40. Explanations for this diversity of species include the isolation of ancestral populations in refugia of humid forest during the quaternary period, the Andean cordilleras as geographical barrier, and the appearance of the Isthmus of Panama. Biology systematics and evolution of the verrucarum group is reviewed with emphasis on the 19 species extant in Colombia.