Transmembrane Protein 50A (TMEM50A)

TMEM50A is located in the RH gene locus, between the RHD and RHCE genes. The function of its protein product is unknown; however, its sequence has potential transmembrane domains suggesting that it may be an integral membrane protein. Its position between the RH genes suggests that polymorphisms in this gene may be tightly linked to RH haplotypes and may contribute to selective pressure for or against certain RH haplotypes.  The authors suggested that functionally relevant mutations of the SMP1 gene may cause selection pressure for or against specific RH haplotypes. Such factors might explain some previously unresolved issues of RH haplotype distribution, such as the high frequency of RH-negativity in the European population.