H. Harigae et al., A novel mutation of the erythroid-specific delta-aminolaevulinate synthasegene in a patient with X-linked sideroblastic anaemia, BR J HAEM, 106(1), 1999, pp. 175-177
A novel missense mutation, A1754G, in exon 11 of the erythroid-specific del
ta-aminolaevulinate synthase gene (ALAS2) was identified in a Japanese male
with sideroblastic anaemia. ALAS activity in bone marrow cells of the pati
ent was reduced to 53.3 % of the normal control. Consistent with this findi
ng, activity of a bacterially expressed ALAS2 mutant protein harbouring thi
s mutation was 19.5% compared with the normal control, but was increased up
to 31.6% by the addition of pyridoxal 5'-phosphate (PLP) in vitro. RFLP an
alysis with Bsp HI restriction revealed that his mother was a carrier of th
e mutation. These findings suggest that A1754G mutation was inherited in th
is family in a manner consistent with X-linked inheritance, and is responsi
ble for sideroblastic anaemia in the patient.