Heterozygosity double

Wright S. D., Michaelides K., Johnson D. J. D., West N. C., Tuddenham E. G. D. Double heterozygosity for mutations in the platelet glycoprotein IX gene in threee siblings with Bemard-Soulier syndrome. Blood 1993 81,2339-47. 

The newborn with Hb-H disease produces about 25% Hb-Bart s and only small quantities of Hb-H. This 74 is slowly disappearing during the first 6 months of life. Small amounts of a 84 component have also been isolated from blood of adult patients with Hb-H disease (D3). The clinical, biochemical, and hematological manifestations are indeed consistent with the hypothesis that Hb-H disease results from a double heterozygosity for the a-Th, and the a-Thj genes. 

Mil. Matioli, G., and Zuckerkandl, E., Microspectrophotometric studies of individual erythrocytes from thalassemia patients. I. A case of double heterozygosity for /3 thalassemia and panglobinopenia. Blood 24, 420-431 (1964). 

Double heterozygosity for glucose-6-phosphate dehydrogenase deficiency. 

Wadman, 1971). The possibility of double heterozygosity in these patients has been suggested (Scriver and Rosenberg, 1973 Zaleski etal, 1973). Other variant forms are much more rare, with a mild variant and patients with thiamin-responsive forms of the disease being described (Scriver and Rosenberg, 1973 Dancis and Levitz, 1978 Duran era/., 1978b Pueschal era/., 1979). A patient with valine toxic intermittent maple syrup urine disease has also been described (Zipf era/., 1979). 

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