Here, we performed a targeted sequencing study of the coding regions of 16 genes involved in HDR (BARD1, BRCA1, BRCA2, BRIP1, ERCC4, FANCM, PALB2, RAD51B, RAD51C, RAD51D, SLX4) or MMR (MLH1, MSH2, MSH6, PMS2, and the related MUTYH), respectively, and compared the mutational spectra between Kazakh patients with EC and Kazakh patients with BC from the same center. This evidence concerns the gene SLX4 and breast cancer.