Figure 5.19. An example of human pedigree analysis.

Figure 5.19An example of human pedigree analysis

(A) The pedigree shows inheritance of a genetic disease in a family of two living parents and six children, with information about the maternal grandparents available from family records. The disease allele (closed symbols) is dominant over the healthy allele (open symbols). The objective is to determine the degree of linkage between the disease gene and the microsatellite M by typing the alleles for this microsatellite (M1, M2, etc.) in living members of the family. (B) The pedigree can be interpreted in two different ways: Hypothesis 1 gives a low recombination frequency and indicates that the disease gene is tightly linked to microsatellite M; Hypothesis 2 suggests that the gene and microsatellite are much less closely linked. In (C), the issue is resolved by the reappearance of the maternal grandmother, whose microsatellite genotype is consistent only with Hypothesis 1. See the text for more details.

From: Chapter 5, Mapping Genomes

Cover of Genomes
Genomes. 2nd edition.
Brown TA.
Oxford: Wiley-Liss; 2002.
Copyright © 2002, Garland Science.

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