Claim: ABC genes (sequence of nucleotides in DNA) transport various molecules across extra-and intra-cellular membranes and ABC proteins (nutrients) are divided into five distinct subfamilies.
Evidence: ABC proteins transport various molecules across extra- and intra-cellular membranes. ABC genes are divided into seven distinct subfamilies (ABC1, MDR/TAP, MRP, ALD, OABP, GCN20, White).