Symptomatic erythrocytosis associated with a compound heterozygosity for Hb Lepore-Boston-Washington (δ87-β116) and Hb Johnstown [β109(G11)Val→Leu, GTG>TTG].

Symptomatic erythrocytosis associated with a compound heterozygosity for Hb Lepore-Boston-Washington (δ87-β116) and Hb Johnstown [β109(G11)Val→Leu, GTG>TTG].