Haemoglobin Tunis‐Bizerte: a new a globin 129 Leu–> Pro unstable variant with thalassaemic phenotype
1995; Wiley; Volume: 90; Issue: 1 Linguagem: Inglês
10.1111/j.1365-2141.1995.tb03382.x
ISSN1365-2141
AutoresR Darbellay, Sara Mach‐Pascual, Karen E. Rose, J D Graf, P Beris,
Tópico(s)Iron Metabolism and Disorders
ResumoA Leu– Pro substitution at position 129 of the ci globin gene was detected in three members of a Tunisian family by sequencing the whole a 2 and i DNA. The mutation was verified by dot‐blot allele‐specific hybridization as well as by digestion of PCR and RT‐PCR products with Nci I, since the aj 129 T_>c mutation creates an additional recognition site for the above‐mentioned enzyme. The Q, i i29(Hi2)Leup ro substitution disturbs helix H resulting in a‐thal trait most probably because the unstable a‐globin chain variant cannot form a/3 dimers. A search for the abnormal Hb and for the abnormal a globin chain by isoelectric focusing, carboxymethyl cellulose chromatography and electrospray ionization mass spectrometry was negative. In the heterozygous state, the Qi i29(Hi2) Leu‐Pro var j ant is man if es t e d by microcytosis (MCV73fl), whereas in the homozygous state there is moderate anaemia with marked microcytosis (Hb 11–6 g/dl, MCV 65 fl).
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