Intrachromosomal mapping of the human alpha-globin gene cluster

Lavinha, Joao Manuel Lopes Borges (1983) Intrachromosomal mapping of the human alpha-globin gene cluster. MSc(R) thesis, University of Glasgow.

Abstract

The aim of this study was twofold. Firstly, to confirm and, if possible, to narrow the regional localization of the human alpha-globin gene cluster on the short arm of chromosome 16. Secondly, to test the value of an experimental approach combining somatic cell genetics and recombinant DNA procedures for human gene mapping. Fourteen informative clones from somatic cell hybrids (derived from human fibroblasts fused with mouse LA9 cells) were produced and phenotypically characterized in terms of their human chromosome content by cytogenetic and isozyme analysis. The four human parental cell types used in this study carried a balanced translocation involving chromosome 16 and chromosomes 2, 5, 9 and 17. These had been cytogenetically interpreted as follows: t(2:16)(2q37:15q11), t ( 5 : 16)(5p11:16p11), t(9:16)(9q22: 16q22) , and t(16:17) (16q12:17p11) . The expression of the selectable marker APRT enabled the clones from somatic cell hybrids to be selected for and against the long arm of HC 16 (AA selection and DAP selection). Combining the cytogenetic and biochemical data on this panel of hybrid clones made it possible to assign APRT and DIA4 to 16q12q22 and PGP to 16p11pter. The DNAs from the hybrid clones, as well as those from both parental origins, were screened for the presence of the human alpha-globin gene cluster. Molecular hybridization on solid phase (Southern blotting) with a 32P-labelled human genomic DNA probe (the recombinant plasmid alphaP7(alpha1)) was used in the screening. A positive association (at a level of significance of 5%) between the presence/absence of the short arm of HC 16 and the presence/absence of the human alpha-globin gene cluster was found. It is therefore concluded that the experimental approach combining somatic cell hybridization and DNA hybridization on solid phase can be successfully applied to the intrachromosomal mapping of cloned single copy genes. The value of different methods such as molecular hybridization in solution, in situ molecular hybridization and trisomy mapping, in assigning single copy genes to chromosome regions is discussed taking the human alpha-globin gene cluster as the model system. The setting up of a bank of somatic cell hybrids and the molecular characterization and prenatal diagnosis of haemoglobinopathies are suggested as prospects for further work.

• Item Type: Thesis (MSc(R))
• Qualification Level: Masters
• Additional Information: Adviser: Malcolm A Ferguson-Smith
• Keywords: Genetics
• Date of Award: 1983
• Depositing User: Enlighten Team
• Unique ID: glathesis:1983-72035
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 17 May 2019 13:18
• Last Modified: 17 May 2019 13:18
• URI: https://theses.gla.ac.uk/id/eprint/72035