C to T transition at the first nucleotide of codon 63 of the β-globin gene corresponding to hemoglobin M-Saskatoon in an Indonesian boy

Abstract

SummaryHemoglobin (Hb) M-Saskatoon, a ~ variant of methemoglobin, is characterized by mild hemolysis. It is caused by the substitution of a histidine by a tyrosine at the 63rd amino acid residue of the f3-globin chain. Amplification and sequence analysis of genomic ~-globin DNA from an Indonesian boy diagnosed as having the more severe disease thalassemia demonstrated the presence of a C to T transition at nucleotide 473 in one of the two f3-blogin genes resulting in a histidine to tyrosine substitution at 63rd residue. This amino acid change matched with that reported in Hb M-Saskatoon. This nucleotide change abolished a recognition site for the restriction endonuclease NlaIII. NlaIII digestion of the corresponding f3-globin DNA amplified from the patient's parents indicated that the mutation was inherited through from his mother. This result shows that the world-wide distribution of Hb M-Saskatoon extends to Indonesia, where it was not previously identified. Possible causes of the unusually severe symptoms observed in the case are discussed.

Persistent Cyanosis in a 4 Month Old Infant with Severe Pneumonia and Haemoglobin M

“…The abnormal globin chains are maintained in the ferric form and cannot undergo reversible oxygenation [4,7] . This rare condition has been described in single individuals or families [5,7,10,11] , without geographic cumulation. In Central Europe it is particularly observed in the domestic population with a high rate of spontaneous mutations.…”

First Observation of Hemoglobin M Saskatoon (�63 (E7) His>Tyr(C-T)) in the Iraqi Population

“…Hemoglobin M Saskatoon (ß63 His>Tyr(C-T)) is a rare hemoglobin variant that was first reported in Japan, fol- lowed by the US, Indonesia, Algeria, Russia, India, and Germany [1,2,3,4,5,6,7,8]. It was also reported in combination with another variant—Hb Hamilton [9]; however, it has yet to reported in the Turkish population [10,11].…”