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E Llop

Publications and source records attributed to E Llop.

At least 19 recordsLinked to original sources
PubMed1994

[Genetic composition of the Chilean population: the Yamanas from Ukika].

The genetic composition of a group of 24 Yamana indians that survive in Puerto Williams, Navarino Island, Chile (parallel 55 south of Tierra del Fuego), was studied. Results showed that these indians have a different genetic composition than Pehuenche indians, specially for HLA system and esterase D. This fact validates the hypothesis, based on archeological and anthropological evidence, about the paleoindian origin of Yamanas.

Blood Group Antigens↗
PubMed1994

[Genetic composition of the Chilean population: the population from San Pedro de Atacama].

This work describes the genetic composition of atacameños from San Pedro de Atacama. The results show that a) the contribution of non-indigenous genes is relatively low, in relation to the spanish immigration period. b) the Hardy-Weinberg genetic disequilibrium for MNSs system should have biological implications c) the variant for esterasa D enzyme may be the same found in other chilean populations.

Blood Group Antigens↗
PubMed1994

[Alcoholism and heredity. A critical update].

The etiology of alcoholism is under constant revision. This work critically examines the accumulated evidence on the degree of genetic determination of alcoholism, aiming to provide an updated view of the problem. The methodological aspects of studies performed in families, twins and adopted siblings are analyzed. The associations of alcoholism with genetic markers and diseases are reviewed, including the negative correlation between alcoholism and an aldehyde dehydrogenase variant in Japanese subjects. The association between marker genes, specially the HLA system, with organic damage and the future projection of these studies are mentioned.

Alcoholism↗
PubMed1993

[Genetic composition of Chilean population: the Pehuenches from Trapa-Trapa].

This study describes the genetic composition of Pehuenche indians from Trapa-Trapa. The admixture analysis revealed that this group has conserved most of its pre-Columbian gene pool and therefore, is representative of the indians that lived in Southern Chile before the Spanish conquest. A relatively high frequency of a esterase D variant seems to indicate that this is a Chilean aboriginal population marker. The Chilean Pehuenches are genetically similar to their Argentinean relatives, which is not surprising since this last group crossed the Andes Mountains in historic times.

Blood Group Antigens↗
PubMed1992

[Genetic evidence corroborates Negme's hypothesis about the greater mildness of American trypanosomiasis in Chile].

Chagas disease is present in northern and central Chile. Not more than 25% of infected individuals have had a pathologic condition presumably due to Trypanosoma cruzi. The majority of individuals with chronic infectious Chagas disease in Chile are asymptomatic in contrast to what has been observed in other South American countries. Historic and paleopathologic evidences suggest that this particular behavior could be explained by a genetic adaptation of Chilean aborigines to T cruzi. Associations between ethnic admixture, presence of Chagas disease, associated cardiac pathology and 4 blood groups (ABO, MNSs, Rh and Duffy) were investigated among inhabitants of San Pedro de Atacama in northern Chile. Cardiac pathology was determined by positive serologic reactions in individuals with abnormal electrocardiographic findings. Individuals with negative serologic results had a significantly greater aboriginal admixture (88%) compared to those with positive serology (66%). This findings supports the hypothesis of genetic adaptation explaining mildness of Chagas disease in Chile.

Adaptation, Physiological↗
PubMed1991

[HLA antigens in Chagas cardiomyopathy: new evidence based on a case-control study].

We studied the distribution of HLA, B and C antigens in 73 Chagasic subjects with and without heart disease. Both groups were matched for age, sex, birth place and history of family residence. Thirty two subjects without evidence of Chagasic infection, with and without heart disease and matched for the same variables were also studied. Compared to all other groups, a significant increase in the level of the B40 Cw3 antigen combination was found in Chagasic subjects without evidence of heart disease.

Adult↗
PubMed1988

A note on the presence of blood groups A and B in pre-Columbian South America.

The results of ABO typing in Chilean mummies, a review of published South American paleoserological studies and a systematic discrepancy of admixture estimates based on ABO and Gm genes support the hypothesis that Andean pre-Columbian populations possessed the A (and perhaps the B) gene in small frequencies.

ABO Blood-Group System↗
PubMed1988

HLA antigens in cardiomyopathic Chilean chagasics.

The distribution of HLA antigens in a sample of 124 Chagas serologically positive Chilean individuals was studied. The sample was subdivided according to the presence or absence of chagasic cardiomyopathy, in order to search for genetic differences associated with this pathological condition. The frequency of antigen B40 in the presence of antigen Cw3 was found to be significantly lower in subjects with cardiomyopathy. We tentatively suggest that the presence of these antigens among noncardiomyopathics is associated with a decreased susceptibility to develop chagasic cardiomyopathy in the Chilean population.

Adult↗
PubMed1984

Microevolution in prehistoric Andean populations: chronologic nonmetrical cranial variation in northern Chile.

Multivariate distance statistics were computed from 14 nonmetrical cranial variables among five prehistoric samples representing steps in the microevolutionary history of a coastal population in northern Chile. Roughly 70% of nonmetrical cranial variation was found to be explained by chronologic distance covering a period of 6,500 years. This estimate is similar to a previous one derived from craniometric data. Implications of these findings are briefly discussed.

Adult↗
PubMed1984

Erythrocyte and HLA antigens of Atacameño Indians.

The present study reports the results of erythrocyte antigen typing for the following systems: ABO, MN, Rh, Kell, Duffy, and Diego in roughly 180 Atacameño Indians from the oasis of Toconao, northern Chile. A subsample was tested for variation at the histocompatibility loci A, B, and C. Results agree with previous findings based on smaller samples. Caucasian admixture of the Atacameño from Toconao was estimated to be 0.056 +/- 0.022.

Blood Group Antigens↗
PubMed1982

Dermatoglyphic characters and physique: a correlation study.

The association of anthropometrics, particularly hand measurements, with dermatoglyphic characters is quantified. Children with square hands exhibit higher main line indices, a-b ridge counts, and more open atd angles. Adults with broader hands have more arches. Taller individuals with larger hands present higher a-b ridge counts and leaner subjects with long narrow hands, closer atd angles. The correlation of physique and dermatoglyphics is small but if verified, suggests that at early fetal stages, factors responsible for the establishment of dermatoglyphic patterns interact with genetic determinants of adult shape that are already active.

Adult↗
PubMed1982

Microevolution in prehistoric Andean populations: I. Chronologic craniometric variation.

Mahalanobis D2 statistics (with size and shape components) were computed for nine craniometric variables among five prehistoric groups representing steps in the microevolutionary history of a coastal population in Northern Chile. Roughly 80% of craniometric variation was found to be explained by chronologic distance covering a period of roughly 6500 years. Kinship decreases in this population at a relatively constant rate of 8.6 X 10(-5) per year.

Biological Evolution↗
PubMed1977

The Chipaya of Bolivia: Dermatoglyphics and ethnic relationships.

Dermatoglyphic data on 15 traits (digital arches, digital radial loops, digital ulnar loops, digital whorls, I loops, Ir loops, H loops, H loops, III loops, IV loops, mainline C absence, total ridge count, a-b ridge count, atd angle, and mainline index) are presented for 141 Chipaya Indians of Bolivia. Ethnic relationships of these Indians to nine South American Indian tribes (Alacaluf, Atacameño, Aymara, Cashinahua, Chácobo, Chama, Chané, Quechua, and Sirionó) are explored by means of a genetic distance analysis using 21 alleles. Genetic distances are complemented with linguistic and geographic distances between the Chipaya and the other tribes. Genetic distances were found not to be significantly correlated with linguistic and geographic distances. Combining the information available, it is concluded that the Chipaya are most likely ethnically related to the Arawak speakers of the tropical forest.

Bolivia↗
PubMed1977

A collation of marker gene and dermatoglyphic diversity at various levels of population differentiation.

The use of dermatoglyphic traits to describe interpopulational diversity among human populations at various levels of differentiation is compared with similar analysis of gene frequency data by means of nonparametric methods employing distance matrices and dendrograms, and by a partition of total variability into its between and within population components. Congruence of dermatoglyphics and gene markers appears to vary with level of population differentiation -- the association remains insignificant until racial level of differentiation is considered. Different pitfalls of the data used are mentioned. The interpretation of these findings is discussed by comparison with other non-human studies.

Biological Evolution↗