Figure 2

Examples of Southern blot results. Genotyping using FMR1 probe: After EcoRI /EagI double digestion, normal females exhibit two fragments, a ~2.8 kb (active X) and a ~5.2 kb (inactive X), while in normal males only a ~2.8 kb fragment is seen: (a) FXS male mosaic for a 51 CGG allele and a full mutation; (b) Premutated FMR1 male (110 CGGs); (c) Klinefelter with two FMR1 normal sized-alleles, showing the active and the inactive X-chromosome; (d) Normal FMR1 male (19 CGGs); (e) Premutated FMR1 male (58 CGGs). Genotyping using AFF2 probe: Following AflIII /NotI double digestion, normal females present two fragments, a ~2.2 kb (active X) and a ~4.8 kb (inactive X), whereas normal males exhibit only a ~2.2 kb fragment: (f) Intermediate AFF2 male (47 CCGs); (g) Premutated AFF2 male (68 CCGs); (h) Homoallelic female [(CCG)₁₄/(CCG)₁₄].