DO_rare_slim NCIthesaurus has material basis in disease has basis in autosomal recessive disease chromosomal deletion syndrome thrombocytopenia-absent radius syndrome A chromosomal deletion syndrome that is characterized by absence of the radius bone and platelet deficiency and bilateral absence of the radii with the presence of both thumbs and generally transient thrombocytopenia (less than 50 platelets/nL) and that has_material_basis_in compound heterozygosity for a rare null mutation involving the RBM8A gene on chromosome 1q12 on 1 allele and 1 of 2 low-frequency noncoding single-nucleotide polymorphisms in RBM8A on the other. UMLS_CUI:C0175703 ORDO:3320 SNOMEDCT_US_2025_09_01:85589009 ICD10CM:Q87.2 MESH:C536940 DOID:14699 MIM:274000 OMIM mapping confirmed by DO. [LS]. Radial aplasia-thrombocytopenia syndrome Thrombocytopenia with absent radii (TAR) syndrome disease_ontology NCI:C99038 syndrome autosomal recessive inheritance symptom