FANCA and Bone marrow hypocellularity: Among other FA genes, FANCB is associated with more severe phenotypes, including early-onset bone marrow failure and extensive developmental abnormalities, most notably vertebral anomalies, anal atresia, cardiac defects, tracheoesophageal fistula, esophageal atresia, renal and limb abnormalities, and hydrocephalus (VACTERL-H) (38–42).