Caste variation in the distribution of placental alkaline phosphatase genes among the Hindus of West Bengal

The effect of parity on placental weight and birth weight: Interaction with placental alkaline phosphatase polymorphism

The effect of parity on placental weight and birth weight is examined through a series of birth records from an Indian population in Calcutta. Placental weight and birth weight increase with parity, the maximum increment occurring between parities 1 and 2. This is compatible with a hypothesis of sensitization of the mother to foetal, paternally derived, antigens. The three common placental alkaline phosphatase enzymic genotypes have no effect on determining foetal development.

Relationship between subunit size and number of rare electrophoretic alleles in human enzymes

Data from published sources were used to compare the numbers of different electrophoretic alleles of 29 monomeric and dimeric human enzymes to their respective subunit molecular weights. Only those human enzymes were considered for which the total sample sizes were in excess of 2000 individuals. Correlations between these two variables were determined within sample size ranges of 2000 less than or equal to n less than or equal to 3000 and 4000 less than or equal to n less than or equal to 5000 individuals, and separately by quaternary class. There was no statistically significant correlation observed for the smaller sample size range in monomers; however, the correlations for the larger sample size range in monomers and both ranges in dimers were significant. Since there is no relationship between subunit size and heterozygosity, the relationships are due primarily to the incidence of rare alleles. These findings demonstrate the effect of locus-specific mutation rates, expected as a consequence of variation of cistron sizes, and imply that other forces are responsible for the relative frequencies of common alleles at some of the loci.

Placental enzyme polymorphism among Maharashtrians: alkaline phosphatase and lactate dehydrogenase

The distribution of placental alkaline phosphatase and lactate dehydrogenase types in 635 placentas from various endogamous groups of Maharashtra have been studied by starch gel electrophoresis. In the case of alkaline phosphatase, 6 common phenotypes and 6 rare phenotypes (F2I1, S1S2, S2S3, I1S2, F1S2, F1I2) are encountered. The highest frequency of Pls1 allele (0.7394) and lowest frequency of Pli1 allele (0.0246) have been found in the Nava-Budha. 6 cases of Cal-1 and 5 cases of Cal-2 types of LDH variants have been observed in the total samples, and Muslims possess the highest frequency of Cal-1 types (3.64%). Population groups are compared with respect to Pl alleles.