This figure shows the normal regions (in white) detected by NSA within the chromosome X from the GIGAS HapMap dataset. These data (70 samples hybridized to GenomeWideSNP 6.0 array) were preprocessed with ACNE. Note that the index of SNPs is ordered by genomic position and the index of samples is ordered by “normal” content. According to this order, the first 32 samples are men and the next 38 are women. In addition, female samples can be separated into two groups. The first group, that presents many uniparental disomy regions, belongs to Asian women (except one caucasian) and the second group belongs to caucasian and Yoruban women.