Insights into the Y chromosome human diversity in Uruguay.

Background: With regard to the origin of its population and microevolutionary processes, Uruguay exhibits distinctive features that distinguish it from other countries in Latin America, while at the same time sharing several similarities. In this article, we will focus on the variability of paternal genetic lineages in two geographical regions with different histories that can be considered as examples of distinct populations for the continent. In general terms, the genetic diversity is a result of different demographic processes related to the American conquest and colonisation.

Oxytocin system polymorphisms rs237887 and rs2740210 variants increase the risk of depression in pregnant women with early abuse.

Prepartum depression is associated with early adversity, pregnancy complications, preterm delivery, postpartum depression, and long-term effects on child neurodevelopment. The oxytocin (OXT) system is affected by early adverse experiences and has been associated with depression. In the current study, we investigated risk factors for prenatal depressive symptoms, mainly the effects of early childhood and adolescence trauma, in combination with the presence of certain variants of polymorphisms of OXT and OXT receptor (OXTR) genes.

Ancestry and TPMT-VNTR Polymorphism: Relationship with Hematological Toxicity in Uruguayan Patients with Acute Lymphoblastic Leukemia.

6-Mercaptopurine (6-MP) is a thiopurine drug widely used in childhood acute lymphoblastic leukemia (ALL) therapy. Genes such as and have an outstanding role in 6-MP metabolism. Mutations in both genes explain a significant portion of hematological toxicities suffered by ALL Uruguayan pediatric patients.

Investigating DNA methylation as a potential mediator between pigmentation genes, pigmentary traits and skin cancer.

Pigmentation characteristics are well-known risk factors for skin cancer. Polymorphisms in pigmentation genes have been associated with these traits and with the risk of malignancy. However, the functional relationship between genetic variation and disease is still unclear.

Discovery of novel DNA methylation biomarkers for non-invasive sporadic breast cancer detection in the Latino population.

Human diversity is one of the main pitfalls in the development of robust worldwide biomarkers in oncology. Epigenetic variability across human populations is associated with different genetic backgrounds, as well as variable lifestyles and environmental exposures, each of which should be investigated. To identify potential non-invasive biomarkers of sporadic breast cancer in the Uruguayan population, we studied genome-wide DNA methylation using Illumina methylation arrays in leukocytes of 22 women with sporadic breast cancer and 10 healthy women in a case-control study.

Genomic Diversity in Sporadic Breast Cancer in a Latin American Population.

Among Latin American women, breast cancer incidences vary across populations. Uruguay and Argentina have the highest rates in South America, which are mainly attributed to strong, genetic European contributions. Most genetic variants associated with breast cancer were described in European populations.

Effect of 15 BMI-Associated Polymorphisms, Reported for Europeans, across Ethnicities and Degrees of Amerindian Ancestry in Mexican Children.

In Mexico, the genetic mechanisms underlying childhood obesity are poorly known. We evaluated the effect of loci, known to be associated with childhood body mass index (BMI) in Europeans, in Mexican children from different ethnic groups. We performed linear and logistic analyses of BMI and obesity, respectively, in Mestizos and Amerindians (Seris, Yaquis and Nahuatl speakers) from Northern ( = 369) and Central Mexico ( = 8545).

Transcriptomic analysis of fetal membranes reveals pathways involved in preterm birth.

Background: Preterm birth (PTB), defined as infant delivery before 37 weeks of completed gestation, results from the interaction of both genetic and environmental components and constitutes a complex multifactorial syndrome. Transcriptome analysis of PTB has proven challenging because of the multiple causes of PTB and the numerous maternal and fetal gestational tissues that must interact to facilitate parturition. The transcriptome of the chorioamnion membranes at the site of rupture in PTB and term fetuses may reflect the molecular pathways of preterm labor.

Associations between male infertility and ancestry in South Americans: a case control study.

Background: Infertility affects 15% of human couples, with men being responsible in approximately 50% of cases. Moreover, the aetiology of male factor infertility is poorly understood. The majority of male factor infertility remains idiopathic and potentially genetic in origin.

Prevalence of EGFR Mutations in Lung Cancer in Uruguayan Population.

Background: Incorporation of molecular analysis of the epidermal growth factor receptor (EGFR) gene into routine clinical practice represents a milestone for personalized therapy of the non-small-cell lung cancer (NSCLC). However, the genetic testing of EGFR mutations has not yet become a routine clinical practice in developing countries. In view of different prevalence of such mutations among different ethnicities and geographic regions, as well as the limited existing data from Latin America, our aim was to study the frequency of major types of activating mutations of the EGFR gene in NSCLC patients from Uruguay.

Interactions between environmental factors and maternal-fetal genetic variations: strategies to elucidate risks of preterm birth.

Context: Preterm birth (PTB) is a complex disease in which medical, social, cultural, and hereditary factors contribute to the pathogenesis of this adverse event. Interactions between genes and environmental factors may complicate our understanding of the relative influence of both effects on PTB. To overcome this, we combined data obtained from a cohort of newborns and their mothers with multiplex analysis of inflammatory-related genes and several environmental risk factors of PTB to describe the environmental-genetic influence on PTB.

Effect of genetic ancestry on leukocyte global DNA methylation in cancer patients.

Background: The study of genetic variants alone is not enough to explain a complex disease like cancer. Alterations in DNA methylation patterns have been associated with different types of tumor. In order to detect markers of susceptibility for the development of cutaneous melanoma and breast cancer in the Uruguayan population, we integrated genetic and epigenetic information of patients and controls.

Breast cancer risk and genetic ancestry: a case-control study in Uruguay.

Background: Uruguay exhibits one of the highest rates of breast cancer in Latin America, similar to those of developed nations, the reasons for which are not completely understood. In this study we investigated the effect that ancestral background has on breast cancer susceptibility among Uruguayan women.

Methods: We carried out a case-control study of 328 (164 cases, 164 controls) women enrolled in public hospitals and private clinics across the country.

Rapid multiplex high resolution melting method to analyze inflammatory related SNPs in preterm birth.

Background: Complex traits like cancer, diabetes, obesity or schizophrenia arise from an intricate interaction between genetic and environmental factors. Complex disorders often cluster in families without a clear-cut pattern of inheritance. Genomic wide association studies focus on the detection of tens or hundreds individual markers contributing to complex diseases.

Frequencies of the four major Amerindian mtDNA haplogroups in the population of Montevideo, Uruguay.

mtDNA Amerindian polymorphisms were studied in 108 inhabitants of Montevideo, Uruguay, using PCR RFLP analysis. Amerindian haplogroups were found in 20.4% of the sample.

Directional mating and a rapid male population expansion in a hybrid Uruguayan population.

The Uruguayan population has been considered as mainly European descent, with a negligible Native American or African contributions. Based on serological and molecular markers, recent studies demonstrate that these two populations had an important influence in the conformation of the present one. To the Northeastern region of Uruguay, a 20% Native American contribution was estimated using autosomal markers and a 62% Native American female origin based on mitochondrial markers.

Characterization of admixture in an urban sample from Buenos Aires, Argentina, using uniparentally and biparentally inherited genetic markers.

In this study we analyzed a sample of the urban population of La Plata, Argentina, using 17 mtDNA haplogroups, the DYS 199 Y-chromosome polymorphism, and 5 autosomal population-associated alleles (PAAs). The contribution of native American maternal lineages to the population of La Plata was estimated as 45.6%, whereas the paternal contribution was much lower (10.

Substantial Native American female contribution to the population of Tacuarembó, Uruguay, reveals past episodes of sex-biased gene flow.

For many years it has been assumed that the population of Uruguay is almost exclusively European-derived and that the biological contribution of the native population as well as of individuals of African descent is negligible. Several recent studies based on a variety of genetic markers, mostly morphological and serological markers, have produced quite a different picture of the constitution of the Uruguayan population. The Native American contribution varies from 1-20%, while the African contribution ranges from 7-15%, in different regions of the country.

Admixture in Hispanics: distribution of ancestral population contributions in the Continental United States.

The effect of gene flow on Hispanic populations from different geographic regions of the United States was analyzed using six autosomal DNA markers (LDLR, GYPA, HBGG, D7S8, GC, and HLA-DQA). By region of sampling, the Hispanic populations showed different ancestry contributions, from a trihybrid structure with European, Native American, and African contributions (California, Nevada, Florida, New Jersey, and Virginia) to a dihybrid structure with European and American contributions (Southwest population) or European and African contributions (Pennsylvania and Southeast population). These findings allowed us to define two regional groups, the West and the East.