Fig. 2

Schematic organization of the AZFb and c loci depicting how the various microdeletions arise. The AZFb and c regions are located in the euchromatic region on the Yq. Both regions share a number of genes [pink box], the genes present in the AZFb region are shown in the green box while the genes present in the AZFc region are present in the blue box. The grey arrows depict the orientation of the genes and the grey bars depict the organisation of the amplicons into palindromes [P1 to P5]. The AZFb and AZFc loci are composed of numerous stretches of ampliconic sequences [block arrows] which are annotated as six colour-coded sequence families (yellow, blue, turquoise, green, red and grey) called amplicons. The size and orientation of the coloured arrows represents the length and orientation of the arrows. AZFb is defined by the P5/proximal P1 deletion (yel3/yel1) which removes 6.23 Mb of DNA and AZFc by the b2/b4 deletion which removes 3.5 Mb of DNA. The partial AZFc deletions b1/b3, b2/b3 and the three variations of the gr/gr deletions [g1/g2], [r1/r3] and [r2/r4] [in dotted box] remove almost half of the AZFc gene content. The shaded block depicts the exact location of the deletion. The information of the map is adapted from published data ([6, 27], and [62])