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C Y Valenzuela

Publications and source records attributed to C Y Valenzuela.

At least 73 records · Page 4Linked to original sources
PubMed1978

Sex dimorphism in adult stature in four Chilean populations.

The sex dimorphism for adult stature is compared in four Chilean populations which differ in their Amerindian ABO blood group composition. Statistical analysis revealed a significant association between sex dimorphism and Amerindian admixture in these populations. Assuming, on one hand, that sex chromosomes have an influence on adult stature and human growth and considering, on the other, that the four populations differ in their X and Y chromosome composition as a consequence of an asymmetrical inter-racial marriage practice, it is postulated that the observed association between sex dimorphism and Amerindian gene composition is a result of this peculiar mating structure.

ABO Blood-Group System↗
PubMedDate not supplied

Month at menarche: a re-evaluation of the seasonal hypothesis.

The hypothesis of a dominant or major seasonal factor that produces the winter peak of menarche found in European girls was tested using several Caucasian and Mongolian samples from the northern hemisphere and two Chilean samples. Present results do not support such a hypothesis. The month at menarche of Chilean girls did not show the expected winter peak; February, a winter month in Europe, showed a deep trough in most samples. Instead, several Mongolian and Caucasian samples from the northern hemisphere clustered according to their ethnic origin rather than to the expected northern hemisphere yearly distribution of photoperiods and temperatures. Other non-seasonal factors seem to explain much better the periodicity of the monthly incidence of menarche. A phylogenetic factor (imprinting) is proposed to explain peaks seen in December and January for Caucasian, Mongolian, Finnish and Chilean samples living in the northern and southern hemispheres. Ontogenetic factors are proposed to explain the highly significant coincidence between the month of menarche and the month of birth, and the modulation of the phylogenetic imprinting by months at which gestation occurred in relation to menarche. The Finnish and Chilean samples, which can be considered mixed Caucasian and Mongolian, showed an intermediate pattern between the Caucasian and Mongolian groups.

Adolescent↗
PubMedDate not supplied

ABO, Rh, MNSs, sex and typhoid fever.

A case-control study on the association between genetic markers (ABO, Rh, MNSs and sex) and typhoid fever (TF) was performed. We found that (a) the B allele conferred protection to females for TF and a mild susceptibility to males; (b) the CDe haplotype (or the RH3 phenotype, mostly CDe/CDe) was associated with protection against Salmonella in both sexes, while cDE (or RH7, mostly cDE/cDE, and RH8, mostly cDE/cde) was associated with susceptibility to TF, and (c) heterozygotes Ss (MNSs system) had a high susceptibility, while SS and particularly ss homozygotes seemed to be protected for the disease. There were very significant interactions among the blood systems and sex.

ABO Blood-Group System↗