question: How many genes does the human hoxD cluster contain?
answer: The human HOXD complex contains nine genes: HOXD1, HOXD3, HOXD4, HOXD8, HOXD9, HOXD10, HOXD11, HOXD12 and HOXD13, which are clustered from 3′ to 5′ in an approximately 100-kb stretch on chromosome 2q31.1 with HOXD1 at the 3' end and HOXD13 the 5′ end.