caa a22 4500 38639282X CHVBK 20180307112125.0 cr unu---uuuuu 161130e198902 xx s 000 0 eng 10.1017/S0016672300027804 doi S0016672300027804 pii (NATIONALLICENCE)cambridge-10.1017/S0016672300027804 Insertion-deletion variation at the yellow-achaete-scute region in two natural populations of Drosophila melanogaster [Elektronische Daten] We have surveyed the region of the X chromosome of Drosophila melanogaster which encodes the yellow, achaete and scute genes for restriction map variation. Two natural populations, one from North Carolina, U.S.A. and the other from southern Spain were screened for variation at about 70 restriction sites and for variation due to DNA insertion or deletion events in 120 kilobases of DNA. Mean heterozygosity per nucleotide was estimated to be 0·0024 and 15 large insertions were found in the 49 chromosomes screened. Extensive disequilibrium between polymorphic sites was found across much of the region in the North Carolina population. The frequency of large insertions, which usually correspond to transposable genetic elements, is significantly lower than has been observed in autosomal regions of the genome. This is predicted for X-linked loci by certain models of transposable element evolution, where copy number is restricted by virtue of the recessive deleterious effects of the insertions. Our results appear to support such models. The deficiency of insertions may in this case be enhanced by hitch-hiking effects arising from the high level of disequilibrium. Copyright © Cambridge University Press 1989 Beech Robin N. Department of Genetics, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh, EH9 3JN, Scotland Brown Andrew J. Leigh Department of Genetics, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh, EH9 3JN, Scotland Genetical Research Cambridge University Press 53/1(1989-02), 7-15 0016-6723 53:1<7 1989 53 GRH https://doi.org/10.1017/S0016672300027804 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0016672300027804 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Beech Robin N. Department of Genetics, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh, EH9 3JN, Scotland NATIONALLICENCE 700 1- Brown Andrew J. Leigh Department of Genetics, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh, EH9 3JN, Scotland NATIONALLICENCE 773 0- Genetical Research Cambridge University Press 53/1(1989-02), 7-15 0016-6723 53:1<7 1989 53 GRH CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge