The beta-thalassemia mutation/haplotype distribution in the moroccan population.

The present study compiles the results of our own research and of a prior study on beta-thalassemia (thal) in Morocco, comprising a total of 187 beta-thalassemic chromosomes. Six major mutations: (beta0) codon 39 (C --> T), (beta+) IVS-I-6 (T --> C), (beta0) frameshift codon (FSC) 6 (-A), (beta0) FSC 8 (-AA), (beta0) IVS-I-1 (G --> A) and (beta+) -29 (A --> G) account for 75.7% of the independent chromosomes studied.

Spectrum of beta thalassemia mutations and HbF levels in the heterozygous Moroccan population.

A comprehensive hematological and molecular analysis of 57 beta thalassemic heterozygotes, 28 homozygotes, 18 double heterozygotes, 3 compound heterozygotes beta thal/beta S and one compound heterozygote beta thal/Hb Newcastle, in 46 Moroccan families with at least one beta thalassemia patient is reported. Six major mutations: beta(0)39 (C-->T), beta(0)FsCD8(-AA), beta(+)IVS1,nt6 (T-->C) and beta(0)IVS1,nt1 (G-->A), beta(0)FsCD6 (-A) and beta(+)-29 (A-->G) cap site account for 75% of the 86 independent beta thal chromosomes studied. For the first time, an extensive mutation/haplotype study has been performed on the Moroccan population, and data are consistent with the geographical location of the country and historical links with both the Mediterranean and the Sub-Saharan Africa communities.

A novel rearrangement of the human fetal globin genes leading to a six gamma-globin gene haplotype.

Haematological as well as gene mapping data are reported for three members of a Portuguese Caucasian family with high G(gamma)-globin levels. A gamma-globin gene sextuplication of the G(gamma)AG(gamma)AG(gamma)AG(gamma)AG(gamma)A(gamma) type was present in the proband and her father. Comparison of gene mapping data with quantitative results of fetal haemoglobin (HbF) analysis provided an explanation for the extremely high G(gamma)-globin levels (> 90%) in the HbF from the two mentioned individuals.

Fetal hemoglobin elevation in Hb Lepore heterozygotes and its correlation with beta globin cluster linked determinants.

We have analysed, at the hematological and molecular level, 51 Hb lepore heterozygotes and three compound heterozygotes for Hb Lepore and HbS (HbLep/HbS) in 26 unselected Portuguese families. The Lepore Boston variant was present in one family, in association with classical haplotype V. All of the other Lepore alleles present haplotype III in association with XmnI (+)5' of (G)gamma gene, in tight linkage disequilibrium to the major mutation found in the Portuguese population, the Lepore Baltimore variant ( delta(68Leu)-beta(84Thr)).

Identification of a new WT1 mutation in a sporadic Wilms' tumour.

A new mutation in WT1 is described in a sporadic unilateral Wilms' tumour consisting of a 17 bp duplication in exon 7 generating a stop codon. The second allele is either partially deleted or presents the same alteration. LOH analysis at 11p15.