M. Banikazemi et al., Localization of the thiamine-responsive megaloblastic anemia syndrome locus to a 1.4-cM region of 1q23, MOL GEN MET, 66(3), 1999, pp. 193-198
Thiamine-responsive megaloblastic anemia (TRMA) is a rare autosomal recessi
ve syndrome characterized by megaloblastic anemia, deafness, and diabetes m
ellitus. A genome scan previously established linkage of this disorder to 1
q23 and haplotype analysis defined a 16-cM critical region. Molecular genet
ic analyses of four unrelated multiplex iranian families inheriting TRMA co
nfirmed linkage to the same region and identified recombinant chromosomes w
hich permitted refinement of the critical region to a narrow 1.4-cM interva
l. The haplotypes of the families differed, consistent with at least two in
dependent mutational events, This refinement of the TRMA locus to less than
10% of that previously published should markedly facilitate the identifica
tion and evaluation of positional candidate and novel genes which may cause
this disorder. (C) 1999 Academic Press.