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J Constans

Publications and source records attributed to J Constans.

17 recordsLinked to original sources
PubMed1978

[Study of the Gc protein in several French population samples : genetic polymorphism by isoelectrofocusing and quantitative results].

The authors describe the results obtained in an examination by isoelectrofocusing of more than 1,000 serum samples from various regions in France. The autochthonous populations of the north side of the Pyrénées are characterized by a high frequency of the gene Gc2 and a very low frequency of the Gc1F gene. This distinguishes them from the other groups studied (southwestern, northwestern and eastern France). The quantitative analysis of the data emphasizes the difference. These results can only be explained by the interdependance of the genetic and metabolic factors.

Adult↗
PubMed1978

Analysis of the Gc polymorphism in human populations by isoelectrofocusing on polyacrylamide gels. Demonstration of subtypes of the Gc allele and of additional Gc variants.

For the study of the group-specific component (Gc) system, serum samples were examined by polyacrylamide gel electrophoresis and by a newly developed immunofixation isoelectrofocusing procedure. Thereby, a greater extent of polymorphic variation was revealed than was known previously. The allele Gc1 could be subdivided into the alleles Gc1F and Gc1S. The distribution of Gc1 subtypes was very different in three populations (Pygmies, Amerindians, and Pyreneans) examined. New variants of the Gc1 and Gc2 genes were also described in the Amerindians and in the Pygmy population, respectively.

Alleles↗
PubMed1978

GcT (Toulouse): a fast variant of the groupspecific system in an Pyrenean family.

In the course of a genetic investigation carried out in a Pyrenean population, a family with a new allele of the Gc system was found. Electrophoretic analysis revealed a faster migrating variant with a double band pattern. Presumably, this variant represents a mutant of the Gc1 allele. The variant is transmitted as an autosomal codominant trait. This additional allele at the Gc locus is named GcT (TcToulouse).

Alpha-Globulins↗
PubMed1978

Relationship between Hp1S and Hp2 gene frequencies among human populations.

In this work, we present new data on the Hp1alpha- and Hp2alpha-chains polymorphism in different populations. We confirm the singularity of the geographical distribution of the Hp2 alleles in our samples. The analysis of the results shows that a significant correlation exists in the population between the Hp1S and Hp2 gene frequencies. An additional Hp1alpha-chain variant is described in a Pyrenean sample.

Algeria↗
PubMed1977

Group-specific component: evidence for two subtypes of the Gc1 gene.

A new method based on isofocusing electrophoresis in the study of the Gc (group-specific component) polymorphism, revealed differing electrophoretic patterns. These patterns can be explained by the existence of two codominant Gc1 subtypes. This hypothesis is in accordance with several family studies. These subtypes are called Gc1F and Gc1S. Eight hundred samples were analyzed, including three different populations: Caucasoid (a western Pyrenean valley), African (Pygmy Bi-Aka), and AMerindian (Quechua-Aymara, from Bolivia). These two subtype phenotypes cannot be explored with the usual technique. They were present in each population sample studied.

Africa↗
PubMed1977

Polymorphisms of the haptoglobin peptide chains in Pyrenean populations.

This study has analyzed the haptoglobin genotype frequencies in over 900 samples from populations living on the Northern slopes of the Pyrenees. The results emphasize the importance of systematically determining the frequencies of the Hp1S, Hp1F, Hp2SS, Hp2FF, Hp2FS alleles. Hp1S was the predominant allele, the HpIS/Hp1 distribution varying between .5 and .69 as in most European populations. Hp2 alleles were observed in low frequency with differences in geographically distinct samples. Pyrenean populations in the western zones (Basques and Baronnies) were found to contain the Hp2FF allele while those in eastern regions, the Hp2SS allele. We have speculated that Hp2SS is as old as the Hp2FF, arising from southern Mediterranean areas, and suggest that Pyrenean groups have different origins.

Alleles↗
PubMed1976

Serum and red cell enzyme polymorphisms in six Amerindian tribes.

Data are presented on red cell and serum enzyme types in six Amerindian tribes in Central and South America of whom the Siriono, Chipaya and Jicaque are markedly inbred. The data obtained in three systems (AcP, PGM, 6PGD) show aberrant phenotype and gene frequencies in these three tribes by comparison with other Amerindian populations. Uniformity of the results was observed in the following red cell enzymes: AK, G6PD, PGM2, ADA and LDH.

Acid Phosphatase↗
PubMed1975

[A new PiN mutation at the Pi locus in human populations].

By a bidimensional immuno-isofocalisation electrophoresis method a new PiN allel was revealed in 365 samples collected in a Caucasoïd population from a Central Pyrenees Valley (Les Baronnies). Its high frequency (0,151) contributes to the decrease of the PiM one. The different NS, MN and NN phenotypes were formerly classed respectively as MS and MM phenotypes. PiN allel seems to be widely distributed in Mediterranean populations.

Alleles↗
PubMed1975

[Quantitative study of the genetics of haptoglobin levels].

A quantitative study, based on several African and Pyrenean populations led to the estimate of the effect of some factors on haptoglobin rate: it shows an influence of age and electrophoretic phenotype, but no apparent effect of sex. Moreover, this study led to the conclusion that there is heritability of haptoglobin rate.

Age Factors↗
PubMed1975

[The phenotype Hp O in several African and Central American populations].

This work shows the higher probability for some individuals of having Hp O phenotype: that is, children under twelve, and individual carriers of haemoglobin S (haemoglobin D carriers do not present this characteristic). This observation appears as a confirmation of the hypotheses explaining Hp O phenotype as a consequence of haemolytic anaemia. Besides, the test of two genetic models taking into account both Hp O and Hp21 M phenotypes leads to strong difficulties due to a certain irregularity of "haptoglobin" genetic system.

Age Factors↗
PubMed1975

Distribution of haptoglobin subtypes in French Basques.

THE Hl1f, Hp1s and Hp2 gene frequencies were studied in two French population samples: one from the Toulouse area and one from a Basque district. The hp alpha1F and alpha1S polypeptide chains were determined by a simple technique. The observations were in accordance with previous findings in Caucasoid populations. The frequency of the Hp1S gene was slightly higher in the Basque sample than in the group from Toulouse.

France↗
PubMed1975

Polymorphism of the CA-I locus of carbonic anhydrase in baboon.

Polymorphism of erythrocytic carbonic anhydrase was studied by means of the usual technique of starch gel electrophoresis in Papio papio, Papio hamadryas, Papio cynocephalus and Papio anubis. In a sample containing both Papio cynocephalus and Papio anubis, examples of the homozygote CA-Ib/CA-Ib were found. A study of parental transmission established the CA-Ib allelic form.

Alleles↗
PubMedDate not supplied

[Genetical and epidemiological study of uricaemia in a Pyrenean population. (Region of Sault - Pyrérées audoises) (author's transl)].

Serum uric acid levels were determined in 229 individuals of Rodome and 127 individuals of Camurace, in the french Pyrénées. The difference of average levels between these two populations was found to be due very likely to different way of life. Intra-familial correlations suggest a greater importance of environmental than genetic factors on serum uric acid levels.

Adolescent↗