Four tribal populations (Chaudhuri, Vasava, Kotwalia and Gamit) of the Surat District in Gujarat (India) have been investigated for the distribution of 22 polymorphic systems of the blood. The main results of this study are as follows: The allele frequencies show considerable heterogeneity among these populations. From the genetic structure analysis it is seen that only a small fraction of the total gene diversity accounts for genetic differences among them, and the major portion of it is due to genetic variation within them. Analysis of genetic distance according to Nei (1972) reveals that the Vasava and Kotwalia show a rather close genetic relationship, while the Chaudhuri and Gamit differ from both the Vasava and Kotwalia.

Blood Group Antigens↗

PubMedDate not supplied

Chromosomal heteromorphisms in Delhi infants. III. Qualitative analysis of C-band inversion heteromorphisms of chromosomes 1, 9, and 16.

Qualitative analysis of C-band heteromorphisms was carried out in 200 infants (100 males and 100 females) in Delhi, India. Partial inversions minor and half inversions were observed as modal levels for chromosomes 1 and 9 in both sexes. No chromosome 16 with a C-band inversion was observed in the present investigation. A significantly higher incidence of percent inversions for chromosomes 1 and 9 was observed in males than in females. The frequency of heterozygous inversion level combinations for chromosome pairs 1 and 9 were remarkably higher than homozygous combinations both in males and females. Our results are compared with the other reported studies, and the possible role of these heteromorphisms in ethnic/racial variation and in developmental disturbances are discussed.

Chromosome Aberrations↗

PubMedDate not supplied

Y-chromosome length heteromorphisms in Delhi infants.

One hundred and seventy normal male infants from Delhi were studied using the CBG technique to estimate Y-chromosome length heteromorphisms. The median class in Y/F [Y/F = total length of the Y chromosome/average total length of the F group chromosomes (19 and 20)] distribution was 0.75-0.79. The Y/F index in infants varied from 0.60 to 1.16 with a mean of 0.81 and a standard deviation of 0.09. A high incidence for very small (53.5 percent) and small (41.2 percent) categories of Y-chromosome length heteromorphisms was observed. Data were compared with other available reports; also possible mechanisms of the Y-chromosome length heteromorphisms and their role in ethnic/racial variation as well as in developmental disturbances are discussed. It is suggested there may be a need to redefine the long and short Y chromosome in a given population while studying different clinical disorders.

Fetal Blood↗