CORRELATIONS IN MULTI-LOCUS GENETIC SYSTEMS: A MATHEMATICAL MODEL

ABSTRACT A spin model with parallels to a multi-locus genetic model is presented which makes it possible to calculate the correlation between allelic states at any two loci in a population at equilibrium. The main features are: (1) The decay of correlation with distance may be expressed essentially as a linear combination of two exponentials, one of which dominates when the two loci are sufficiently far apart. (2) The correlation between two loci a specified distance apart is increased as the number of loci in the entire system increases. The results are compared with those of other theoretical models and discussed in the light of available experimental data. Possible ways of generalizing the model are outlined. However, additional experimental data is clearly needed to indicate the genetic relevance of work of this nature.

The Preservation of Latex by Acids

It is shown that by the application to field latex of amounts of formic acid of the order of 9 per cent by weight of the latex or 10 per cent by volume of the 90 per cent commercial acid, a product results which will retain its fluidity for long periods. It is, however, apparently micro-flocculated, and unstable. Because of their instability, it seems unlikely that acid latices of this kind will find technical applications. The findings are in no way contradictory to those of Fullerton, whose experiments on coagulation did not include trials with such large amounts of acid. It is regretted that fuller experimental data cannot be given because most of the relevant records were destroyed recently by fire at the Institute. It is probable that a further study will be made, from which additional experimental data together with a possible explanation of the empirical observations given here may emerge.