The great human geneticist JBS Haldane has stated already more than half a century ago that the genetic composition of present day human populations was shaped mainly by infectious diseases of the past. Modern biology and medicine knows the human defence system against infections in great detail; many genes are involved in this system. They are possible candidate genes for associations with human infections. However, studies on these lines are now outside the main stream of research in medical genetics in the industrialised countries of the west since in these countries, most infectious diseases are having a small impact only on morbidity and mortality. In future, this might be quite different since the genetic systems of infective agents are quickly adapting to the ubiquitous presence of chemotherapeutic agents and antibiotics. Therapy resistant germs belong to the major challenges to medical research. Here, a field of research is opening up where scientists in countries such as India could contribute in an original and very useful way to international research, since, in these countries, many infectious and parasitic diseases are still common Leprosy, tuberculosis, and malaria, as well as intestinal parasites may be mentioned as examples. Associations with genetic polymorphisms such as the HLA system or ABO Blood groups have been studied in the past but the designs of most of these studies were quite simplistic. Here, much more sophisticated designs are possible today. For example, in such studies, genetic variation not only of the human host but of the infective agent, as well, should be considered; here, complex population genetic models have to be used A theoretical model will be demonstrated which starts with very realistic assumptions but does not lead to a conventional genetic equilibrium but to regular unulation of gene frequencies in the host. Studies directed at the interplay between the "defence" system of the human host and the genetically determined "attack strategy" of infective agents may lead to a more profound understanding of both partners and, in future, to improved strategies for overcoming infections.

Ever since the discovery of restriction fragment length polymorphism (RFLP) by Kan and Dozy (1978), several significant achievements have been made in DNA polymorphism studies over the past two decades. It is indeed the observation of hypervariable minisatellites as dispersed throughout the genome by Jeffreys et al. (1985a) has added new dimension and that gave the impetus to the prolific application of DNA polymorphism in many fields such as medicine, agriculture, population genetics, and forensic science. Here we enumerate the historical background, basis, analytical approaches and applications associated with DNA polymorphism studies. We also present a detailed account of various DNA probes in vogue such as cloned (single and multilocus) minisatellites/VNTRs, synthetic oligonucleotides and the advantages and limitations of each probe/system. The recent advances made in PCR based DNA typing is also highlighted.

Triangles were constructed on dermatoglyphic whorl patterns by joining the cores and triradii. Several angles were measured, and the correlation among these measurements and the ridge counts war studied. Descriptive statistics and canonical correlations were also computed. The major findings, included a significant positive correlation between the radial / ulnar tangent angle and the radial / ulnar ridge count and a significant negative correlation between the radial / ulnar base angle and the radial / ulnar ridge count.

Two inherited alloalbumins, designated albumin Ropar and albumin Samana were detected. The allele frequency for the variant albumins was found to be 0.0004 in the present study. These variant albumins were compared with some other previously reported alloalbumins.

Acrocentric association in Down Syndrome is a widely debated phenomenon. The present study on a total of 68 subjects from South India revealed that the incidence of Down Syndrome is increased with an increased frequency of association of acrocentric chromosomes in their parents.

Data on 134 cases diagnosed for essential-hypertension (EHT) and studied for eight biochemical and five immunological parameters (blood sugar, blood urea, serum creatinine, serum cholesterol, serum protein, haptoglobin, Lactate dehydrogenase (LDH), ceruloplasmin, Ig-G, Ig-A, antinuclear antibody (ANA) T and B cell populations) along with 180 normotensive controls were computerised for their contributions by using the forward selection procedures of selecting the best regression equation (Draper and Smith, 1981). When biochemical parameters alone were considered, they contributed 10.0 per cent to the variation in diastolic blood pressure of which the contribution due to haptoglobin was 6.59 per cent and serum creatinine 3.41 per cent. When biochemical and immunological parameters were considered, only LDH contributed 15.30 per cent to the variation in diastolic blood pressure. When the data was grouped based on the expected diastolic pressure (mm/Hg;) into low risk (80-100) medium risk (101-110) and high risk (111-120) groups, males were found to be more prone in general. In the medium risk group 30.98per cent and high risk group 27.78per cent of the cases showed Positive family history while all the cases with low risk were non-familial. Among the familial cases compared to males, females were found to be 2.67 times higher in medium and 1.5 times higher in high risk groups suggesting greater involvement of genetic component in females and non-genetic and / or physiological factors in males.