Vol. XXXIII Issue 2
ISSN online version: 1852-6233
ARTICLE 1 - research
VARIABILITY OF PDYN AND OPRK1 GENES IN FOUR ARGENTINIAN POPULATIONS AND ITS GENETIC ASSOCIATION WITH CLINICAL VARIABLES RELATED TO ACUTE POSTSURGICAL PAIN
VARIABILIDAD DE LOS GENES PDYN Y OPRK1 EN CUATRO POBLACIONES ARGENTINAS Y SU ASOCIACIÓN CON VARIABLES CLÍNICAS RELACIONADAS AL DOLOR AGUDO POST-QUIRÚRGICO
Di Santo Meztler G.P., Schiaffi J., Rigalli A., Esteban Torné M.E., Martina P.F., Catanesi C.I.
Several population studies showed an association between variation in pain sensitivity and genetic polymorphisms located in Prodynorphin (PDYN) and Kappa Opioid Receptor (OPRK1) human genes. We analysed polymorphisms of these two genes to characterise their variation in Argentinian populations, as well as to evaluate their association with acute pain sensitivity. We studied 11 genetic markers in individuals from four locations in Argentina (Ciudad Autónoma de Buenos Aires, La Plata, Resistencia, and Misión Nueva Pompeya), calculated the population parameters, and evaluated the possible association among pain sensitivity, clinical, and genetic variables through a Generalised Estimating Equation model. High linkage disequilibrium was observed in the four populations for both genes, and significant differences were found among frequencies of Argentinian populations and those from other continents reported in the 1000 Genomes Project. Four PDYN gene polymorphisms from 3´ untranslated region and exon 4 showed association with acute pain sensitivity. One genotype of each of these polymorphisms was associated with a higher pain sensitivity, probably related with the activation of the N-methyl-D-aspartate (NMDA) receptors. We found a strong association with acute pain for the following clinical variables: 1) time after surgery, 2) intravenous klosidol supplied every 8 h, and 3) type of incision. Our results highlight the importance of a regional study of genetic variants which influence pain sensitivity and analgesic response.
Key words: human populations, pain sensitivity, acute pain, genetic polymorphisms, genetic structure
ARTICLE 2 - research
IMPACT OF GENETIC ANCESTRY ON THE DISTRIBUTION OF INTERFERON-λ4 RS12979860 POLYMORPHISM IN A GLOBAL POPULATION OF BUENOS AIRES, ARGENTINA
IMPACTO DE LA ANCESTRÍA GENÉTICA EN LA DISTRIBUCIÓN DEL POLIMORFISMO DE INTERFERÓN-λ4 RS12979860 EN UNA POBLACIÓN GLOBAL DE BUENOS AIRES, ARGENTINA
Mansilla F.C., Avena S.A., Dejean C.B., Turco C.S., Capozzo A.V.
Human interferon-λ4 is a cytokine involved in early stages of antiviral responses. Strikingly, some allelic variants with diminished antiviral activity reduce the susceptibility to viral infections, thus they would have suffered a positive selection pressure throughout the evolutionary history of the genus Homo. An intronic variant within the IFNλ4 locus (rs12979860, T˃C) emerged as one of the main gene determinants of the response to HCV and other viruses. The rs12979860-C allele has a differential frequency in African, European and Native American populations, though South American data are scarce. Here we characterize for the first time the distribution of rs12979860 genotypes in a sample of the global population of Buenos Aires, Argentina, assessing its association with European, Native American and African parental components. The rs12979860 genotypes were determined by PCR-RFLP in DNA samples from donors of a blood banks of Buenos Aires (n=96), whose genetic individual ancestry (European, African or Native American) had been previously determined using molecular markers. The distribution of rs12979860-CC, CT and TT was 29.17%, 50.0% and 20.83%, respectively. A significant increase in the frequency of CC among donors with a strong European contribution and a greater impact of the Native American component among donors carrying the T allele were observed. Native American and European components were associated to the rs12979860 distribution in a sample of the global population of Buenos Aires, while no differences were directly attributable to the African ancestry. Considering interferon´s key role in antiviral responses, our results may contribute to both bioanthropological and immunogenetic studies associated with infectious diseases.
Key words: ancestry, Buenos Aires, IFNλ4 polymorphism, rs12979860 distribution.
ARTICLE 3 - research
KNOWLEDGE ABOUT GENETICS AND TRUST IN GENETIC TESTING IN A MID-SIZE CITY IN ARGENTINA
CONOCIMIENTO SOBRE GENÉTICA Y CONFIANZA EN PRUEBAS GENÉTICAS EN UNA CIUDAD DE TAMAÑO MEDIO EN ARGENTINA
Mendoza M., Mazza B., Cabana G.S., Smith L., Di Fabio Rocca F., Delfino H., Martínez C.
Public attitudes about genetics appear to depend on the local context. We analyzed survey responses obtained in 2015 from 293 residents of Luján, a city in the province of Buenos Aires, Argentina, who self-assessed their knowledge about genetics and their trust in genetic tests. The survey integrated a larger research project for which consenting adult participants shared demographic and genealogical information and provided saliva samples for genetic ancestry analyses. Participants reported little knowledge but high trust in genetic testing when questioned about knowledge and trust. Well-known media stories of DNA-based forensic genetic investigations to identify the victims of state repression during the military dictatorship may have contributed to the high self-assessment of their genetic knowledge expressed by some participants, regardless of educational attainment. Our analysis provides information that could be used as a baseline to begin unraveling the current level of public trust in genetics in a region of the Global South where genetic testing has become widespread, but people’s knowledge of and trust in genetics remain poorly studied.
Key words: genetic tests, knowledge, public attitudes, trust
ARTICLE 4 - research
CLONAL DETECTION OF Streptococcus agalactiae Lehmann AND Neumann PARENTAL STRAINS BY RANDOM AMPLIFICATION OF POLYMORPHIC DNA
DETECCIÓN CLONAL DE CEPAS PARENTALES DE Streptococcus agalactiae Lehmann y Neumann POR AMPLIFICACIÓN ALEATORIA DE ADN POLIMÓRFICO
Cortese, I.J., Novosak M.G., Oviedo P.N, Cannistraci Giolito R.E. Laczeski M.E.
Streptococcus agalactiae (GBS) causes invasive infections in newborns, being the most frequent the maternal transmission. Epidemiological studies use molecular techniques that assess genetic diversity, including random amplification of polymorphic DNA (RAPD) that is found to be accessible, sensitive and uses arbitrary primers to amplify polymorphic segments of DNA by PCR. The objective was to determine the clonal relationship between GBS strains recovered from mothers and their respective newborns. Four pairs of GBS isolates obtained from vaginal-rectal swabs of mothers and blood cultures of their newborns were studied with RAPD. Primers OPS11, OPB17 and OPB18 were used to select one with the ability to discriminate between non-genetically related strains. The Hunter-Gaston formula that establishes the discrimination index (D) was used; when D>0.90, it is considered that the isolates belong to different clones. The amplification profiles for the eight isolates, using each primer independently, allowed to calculate a D=1 for OPS11, and D=0.84 for OPB17 and OPB18. Therefore, OPS11 was selected for the study of the clonal relationship of the isolates, and similar amplification profiles were found by RAPD for each mother-newborn pair of GBS isolates. Different amplification profiles were observed between pairs of mother-newborn strains, which reveals the discrimination between unrelated strains, confirmed by pulsating field electrophoresis (PFGE). These results indicated vertical transmission for each studied case and robustness of the OPS11 primer. Appropriate conditions of the RAPD trial were found, which is useful for epidemiological studies.
Key words: Streptococcus agalactiae, neonatal disease, molecular epidemiology, RAPD technique, vertical transmission
ARTICLE 5 - research
SELECCIÓN CONTRA DISPLASIA DE CADERA CANINA EN EL OVEJERO ALEMÁN
BREEDING AGAINST CANINE HIP DYSPLASIA IN THE GERMAN SHEPHERD DOG
Canine hip dysplasia (CHD) is a progressive and disabling disorder in large dog breeds, such as the German Shepherd dog. Breeding sires and dams free of dysplasia is the only way to reduce its incidence. Several diagnostic methods have been developed based on radiographic examination, on the basis of which dogs are selected for breeding. CHD has a polygenic hereditary basis and environmental influence, with a median to low heritability (ca. 0,20 to 0,40), so the progress in phenotypic selection has been slow. In Argentina, the prevalence of dysplasia in German Shepherd dogs remains high (> 25%) and it is impossible to predict its incidence in the offspring of the breeding stock. Some countries have implemented a selection based on the estimated breeding value, obtaining an important advance. Genome-wide association studies have revealed numerous CHD-associated markers and several candidate genes have been found that point to the possibility of implementing genomic selection in the near future.
Key words: canine hip dysplasia, German Shepherd dog, phenotypic selection, genomic selection, estimated breeding value
DR. ENRIQUE CURT GADOW