Figure 1.

Relative sizes and positions of the seven human alcohol dehydrogenase (ADH) genes on the long arm of chromosome 4 (i.e., chromosome 4q). They are shown in the direction in which the genes are transcribed (arrows), but this is opposite to their orientation on chromosome 4q (i.e., ADH5 is closest to the region where the chromosome arms are joined [i.e., the centromere]). The distances between the genes are indicated in kilobasepairs (kb).