Figure 1.

Example Genotype Data and IBIS Processing

(A) Genotype data at three markers for four samples (stick figures). The input encodes the alleles at each site as a zero or one, as indicated.

(B) Sets $H_{s,1}^{\left(0\right)}$ and $H_{s,1}^{\left(1\right)}$ for each sample s contain the markers that are homozygous for alleles 0 and 1, respectively.

(C) The set operations to construct W₁ for two of the samples yields one marker where these individuals are homozygous for opposite alleles.

(D) Example W_i values across five windows for a given pair. IBIS detects potential IBD segments as a series of windows where the first and last windows have no inconsistencies and where $\left|W_i\right|\le 1$ for all other windows i. Such a region with no inconsistent genotypes spans windows two through four in the figure.