Isolation of β-globin related genes from a human cosmid library.

A human gene library was constructed using an improved cloning technique for cosmid vectors. Human placental DNA was partially digested with restriction endonuclease MboI; size-fractionated and ligated to BamHI-cut and phosphatase-treated cosmid vector pJB8. After packaging in lambda phage particles, the recombinant DNA was transduced into Escherichia coli 1400 or HB101 followed by selection on ampicillin for recombinant E. coli. 150 000 recombinant-DNA-containing colonies were screened for the presence of the human beta-globin related genes. Five recombinants were isolated containing the human beta-globin locus and encompassing approx. 70 kb of human DNA

Isolation and characterization of the human collagen α1(I)-like gene from a cosmid library.

We have isolated a human collagen alpha 1(I)-like gene from a cosmid library. The clone which contains 37kb of human DNA has been shown to contain this gene by DNA sequencing, hybrid arrest and hybrid selection assays and Northern blot hybridizations. The collagen gene sequence extends through most of the cloned DNA and must, therefore, be at least 35kb in length

Structure and expression of a cloned β o thalassaemic globin gene.

We have cloned the single beta-globin gene from an Italian patient who is a double heterozygote for beta o/delta beta o thalassaemia. RNA isolated from nucleated red cells from this patient can be translated in vitro to give detectable levels of A gamma- G gamma and alpha-globin, but no beta-globin. S1-mapping transcription studies show that beta-globin mRNA is present at about 1-3% of the level of alpha- and gamma-globin mRNA. In addition, the expression of this gene has been studied by reversed genetics. SV40-plasmid-beta o-globin gene recombinants have been transfected into Hela cells and analysed for beta-globin mRNA. In contrast to the results obtained with mRNA isolated directly from the blood of this patient, in the transfected Hela cells the same level of beta-globin mRNA is seen for the beta o thalassaemic globin gene and for a normal beta-globin gene. To elucidate the nature of the lesion, the entire DNA sequence of the beta-globin gene of this patient has been determined. The sequence shows that this gene contains a termination codon at position 39 (CAG - greater than UAG). Otherwise, there is a remarkable conservation of the entire DNA sequence