[Medical genetics services in VenezuelaServiços de genética médica na Venezuela].

Objective: To characterize medical genetics services in Venezuela and describe the distribution of their resources, services, technologies, and professional training.

Methods: A descriptive, documentary study of genetic services was conducted between February and November 2016, involving a review of primary documentary sources and the use of a data collection form in research institutions to obtain information on the availability of human resources, clinical care, and diagnostic services, as well as professional training. Furthermore, the Venezuelan Society of Human Genetics database was used to identify the human resources available in genetics centers.

Paradoxical roles of IFN-gamma in models of Th1-mediated autoimmunity.

T-cell responses to antigens are classified on the basis of the cytokines they produce as either Th1 (IFN-gamma, IL-2) or Th2 (IL-4, IL-10), with these Th types being indicative of either cell-mediated or antibody-mediated responses, respectively. Using this classification, T-cell responses in MHC-class-II-restricted autoimmune diseases appear to be predominantly of the Th1 type, based on the presence of high levels of IFN-gamma. This simplistic classification has recently been challenged, however, as disease incidence and severity are frequently elevated in animals that have a deficient IFN-gamma response.

Genetic ablation of interferon-gamma up-regulates interleukin-1beta expression and enables the elicitation of collagen-induced arthritis in a nonsusceptible mouse strain.

Objective: To determine whether the lack of interferon-gamma (IFNgamma) alters resistance to collagen-induced arthritis (CIA) in a nonsusceptible mouse strain, and if so, to identify changes in the antibody, cellular type II collagen (CII)-specific immune responses, and cytokine gene expression that might account for the altered susceptibility.

Methods: CIA-resistant C57BL/6 and C57BL/6 IFNgamma-/- mice were immunized with bovine CII in Freund's complete adjuvant (CFA) or in CFA alone. Animals were monitored for signs of arthritis for up to 80 days; arthritis severity was assessed visually and histologically.

Extended HLA haplotypes in a Carib Amerindian population: the Yucpa of the Perija Range.

Eleven MHC loci haplotypes have been defined among a Carib speaking Amerindian population; the Yucpa, inhabiting the northern section of the Perija Range, on the limits between Colombia and Venezuela. This tribe has been known with the name of "Motilones mansos" and is located close to the Chibcha-Paeze speaking Bari or "Motilones bravos." Seventy-three full blooded Yucpa living at the villages of Aroy, Marewa, and Peraya, were selected using a genealogy previously collected by an anthropologist and tested for Bf-C4AB complement allotypes and by serology, high resolution PCR-SSO and SBT typing for HLA class 1 and class 2 alleles.

HLA class II associations with rheumatic heart disease are more evident and consistent among clinically homogeneous patients.

Background: Discrepancies in reported HLA class II associations with rheumatic heart disease (RHD) may have been due to inaccuracies of serological typing reagents and/or lack of defined clinical classification of patients analyzed. The molecular association between HLA and RHD was investigated in patients with defined clinical outcome.

Methods And Results: Class II allele/haplotype distribution was determined in 2 groups of RHD patients (n=88) and a control group (n=59).