Molecular and clinical characteristics of Hemoglobin Ottawa detected in a Chinese population

Hemoglobin (Hb) Ottawa [alpha 15 (A13) Gly -> Arg], also known as Hb Siam, was first described in an 82-year-old Canadian in 1974. The same year, a second case was reported in a 28-year-old Chinese male living in Thailand. A third case was found in 1986 in a Chinese female living in the Hubei province of China. Since then, there have been no reports of Hb Ottawa in mainland China in the English literature. Hb Ottawa results from a GGT -> CGT mutation in codon 15 of the alpha(1) or alpha(2)-globin gene. Hb Ottawa carriers do not present any clinical symptoms or hematological changes, and are often diagnosed during a health examination and thalassemia screening. In a hemoglobin survey of 9745 students in Chaozhou, Guangdong, China, we identified four cases of Fib Ottawa in a thalassemia screening by Hb electrophoresis, and confirmed it to be the result of a GGT -> CGT mutation in codon 15 of the alpha(2)-globin gene by DNA sequence analysis.