HLA and MICA Imputation
After imputation of HLA and MICA, we obtained genotypes for 7,078 SNPs in the MHC region (29.6–33.2 Mb at chromosome 6, UCSC Genome Browser hg18), 105 two-digit HLA or MICA alleles, 176 four-digit HLA or MICA alleles, and 438 amino acid polymorphisms encoded by HLA or MICA genes. Imputation of MICA demonstrated high concordance between genotyped and imputed genotypes (88.9% for both two- and four-digit alleles), which was comparable to that reported for imputation of other HLA genes.24–26