The genetic etiology of the founder GP6 mutation found in Chilean patients. (A) Pedigrees showing a pattern of inheritance and different haplotypes surrounding the GP6^InsA mutation site in identified Chilean families. (i-viii), Pedigrees including 6 probands (marked by a P and an arrow) and 2 heterozygous cases, wherein which the DNA of family members was also available for sequencing. For relatives who were not sequenced, we inferred the most likely haplotype based on sequencing results from samples provided; these individuals are marked with an asterisk (∗) and their inferred haplotype, assuming a normal pattern of inheritance and no recombination events, is in italics. (ix-x), Haplotypes of 2 individuals with homozygous mutation in which no DNA of family members was available. Color coding has been used to show inheritance patterns of alleles (block color alleles carry the GP6^InsA haplotype). Squares indicate males, and circles indicate females. Blank shapes indicate GP6^WT/WT status, half-filled shapes indicate GP6^WT/InsA status and filled shapes indicate GP6^InsA/InsA status. (B) Map of Chile indicating geographical sites of origin where patients have been diagnosed (arrowed). Santiago, Chile’s capital city, is indicated in red. Map adapted from www.touropia.com with permission. (C) The position of the microsatellite markers (18xTG and 21xAC), the GP6 exon 6 mutation (clinVar ID number 1072837), and the GP6 common SNP rs1654416 on chromosome 19 are shown. Tables show the relative frequencies of fragment size for each microsatellite marker and SNP status, in the 3 genetic groups investigated. The orange arrow shows the direction of GP6 transcription. HOM = GP6^InsA/InsA, HET = GP6^WT/InsA, WT = GP6^WT/WT. n = 9 for GP6^InsA/InsA, 50 for GP6^WT/InsA and 36 for GP6^WT/WT.