The genetic cause of TAR syndrome was found to have compound mutations with a microdeletion of around 200 bp in the 1q21.1 region of the genome (including RBM8A) on one inherited chromosome, and a low-frequency noncoding SNP in RBM8A on the other inherited chromosome 1 (rs139428292 or rs201779890) [15,17]. The gene discussed is RBM8A; the disease is Thrombocytopenia - absent radius.