Somatic Cell Hybridization in Cytogenetic Analysis

Abstract

For many years, human geneticists dreamed of finding a way to study segregation and recombination in somatic cells, in order to overcome the difficulties of genetic analysis with small families, few genetic markers, limited availability of meiotic material, and no experimental matings. Somatic cell genetics became a powerful way to do this, with the discovery of preferential loss (segregation) of human chromosomes in interspecific human-rodent somatic cell hybrids. The analysis of such hybrids has made it possible to correlate the loss or retention of a specific chromosome or chromosome segment with the loss or retention of a specific gene product or gene, allowing the gene to be mapped to that chromosome or segment. Enormous strides have been made using this approach. It is still one of the most widely used methods for mapping genes and for demonstrating multiple genetic causes of a disease phenotype (genetic heterogeneity). Somatic cell hybrids have many other uses in cytogenetic analysis. It is therefore helpful to understand somatic cell hybridization and how it is achieved experimentally.