X-linked hypogammaglobulinaemia and isolated growth hormone deficiency

X-linked hypogammaglobulinaemia and isolated growth hormone deficiency

A rare X-linked condition (OMIM:307200) characterised by hypogammaglobulinaemia with isolated growth hormone deficiency. Like X-linked agammaglobulinaemia (OMIM:300755), it is caused by defects on BTK, a gene on chromosome Xq21.33-q22 that encodes a protein which plays a central role in B-cell development, differentiation and signalling.