Population Genetics and Aid
The main objective in human genetics is to study variability in man, and the smallest system from which variability may arise is 2 different genes(or allels) for a given locus on a chromosome pair. The two-allele system responsible for cystic fibrosis(CF), a recessive hereditary disease, is shown in Figure 1: If the relative genefrequency is p or 1/40 for the(pathological) CF-allel and q or 39/40 (or virtually 1) for its normal counterpart, we shall expect the following relative frequencies for the 3 possible genotypes in the population: 1/1600(p2) for the patients with CF, about 1/20(2pq) for heterozygotes(or carriers) and somewhat less than 1(q2) for homozygote, normal individuals. These relative frequencies will remain constant for dozens of generations because there is an equilibrium between new mutations or unknown heterozygote-advantages and the gene-loss by an almost zero fertility-rate for CF-patients.
KeywordsCystic Fibrosis Sickle Cell Anemia Myotonic Dystrophy Family Plane Recessive Hereditary Disease
Unable to display preview. Download preview PDF.
- 1.Rasmuson, M. Genetiska risker vid heterolog insemination.L ä kartidninqen, 72:2042–2043, 1975.Google Scholar