β-thalassemia is a common hereditary disorder, particularly in Middle Eastern countries. More than 200 mutations in the β globin gene have been reported; most are point mutations in functionally important regions (HBB; OMIM #141900)). The spectrum of mutations varies significantly between different geographical regions; only a few common mutations of β-globin cause β-thalassemia in each population. The aim of this study was to determine the spectrum of mutations that cause β-thalassemia in the North Coast of Egypt and to investigate their correlation with the phenotypic severity of β-thalassemia. We carried out our study with a total of 47 Egyptian patients (25 male and 22 female) confirmed to have β-thalassemia. Evaluation of β-thalassemia mutations revealed the presence of 10 β-globin mutations. The most frequently encountered mutations were intronic: IVS 1.6 [T>C] (27.66%) and IVS 1.110 [G>A] (22.35%), followed by IVS 2.848 [C>A], IVS 1.1 (G>A), and IVS 2.745 [C>G]. We observed the exonic and promoter mutations less frequently. A homozygous mutation was found in 24 patients (51%) and compound heterozygous mutations were found in 13 patients (28%). However, in 9 patients (19%), we identified only 1 mutation. In 1 patient (2%), we detected no mutation. The detection rate of the method that we used in our population was 88% (83 of the tested 94 alleles). The results we obtained did not reveal any correlation between genotype and phenotype among patients with β-thalassemia.

A high degree of molecular heterogeneneity at the phenylalanine hydroxylase (PAH) locus was established by examining RFLP haplotypes and PAH mutations in the families of 13 Egyptians with phenylketenouria (PKU). Thirteen different haplotypes were unequivocally determined in these kindreds. Haplotypes 1.8, 3.9, 4.3, 7.8, 22.11, 27.6, and 52.8 were found segregating with normal chromosomes, whilst haplotypes 1.8, 5.9, 23.8, 32.8, the newly assigned 73.9, and two as yet incomplete but novel haplotypes were found segregating with the mutant chromosomes. There was no particular preference for a single haplotype among normal or mutant chromosomes. Nine different mutations were also identified among the 26 alleles.

We report on a 2.5-month-old boy with hypertelorism, hypertrichosis, anteverted nostrils, malformed ears, thin lips, downturned corners of the mouth, micrognathia, short neck, cryptorchidism, and bilateral simian creases without limb anomalies. Cytogenetic studies showed a duplication 3q----qter 46,XY,der(6),t(3;6)(q21;p25)pat. The absence of limb anomalies is noteworthy; all 12 previously reported patients with the same duplication had limb anomalies. The uniqueness of this report provokes speculations regarding limb morphogenesis in embryos with chromosome anomalies. The concepts of chronogenetics, heterochrony, and developmental field defects appear relevant to yet another set of patients with chromosome anomalies.

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