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chapter 23

Structure and Properties of DNA

F I G U R E 2 3 - 1 7

A sampling of single-gene defects (Mendelian disorders) that have been mapped to specific chromosomal loci. More

than 8000 inherited disorders and defects have been identified as stemming from mutations in single genes, and many of

the altered base changes have been mapped to specific chromosomal loci. As the analysis of the DNA sequence of the

human genome proceeds, it is expected that eventually thousands more mutated alleles that cause inherited disorders and

defects will be identified and mapped.