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R Semeonoff

Publications and source records attributed to R Semeonoff.

5 recordsLinked to original sources
PubMed1977

Can polymorphism be maintained by selection favouring an intermediate optimum phenotype?

Populations of Drosophila melanogaster containing the special chromosome, M-5, were subjected to artificial selection to canalise scutellar bristle phenotype at four bristles. At the end of the experiment allele frequencies at three enzyme loci were measured. In the selected population, these frequencies were found to have diverged from their starting values less than would have been predicted on the basis of random genetic drift. This was not found in control populations or in populations selected for low bristle number.

Alleles↗
PubMedDate not supplied

Positive identification of an immigration test-case using human DNA fingerprints.

The human genome contains a set of minisatellites, each of which consists of tandem repeats of a DNA segment containing the 'core' sequence, a putative recombination signal in human DNA. Multiallelic variation in the number of tandem repeats occurs at many of these minisatellite loci. Hybridization probes consisting of tandem repeats of the core sequence detect many hypervariable minisatellites simultaneously in human DNA, to produce a DNA fingerprint that is completely individual-specific and shows somatic and germline stability. These DNA fingerprints are derived from a large number of highly informative dispersed autosomal loci and are suitable for linkage analysis in man, and for individual identification in, for example, forensic science and paternity testing. They can also be used to resolve immigration disputes arising from lack of proof of family relationships. To illustrate the potential for positive or inclusive identification, we now describe the DNA fingerprint analysis of an immigration case, the resolution of which would have been very difficult and laborious using currently available single-locus genetic markers.

DNA, Satellite↗