Titus E A, Hsia Y E, Hunt J A
Department of Genetics, John Burns School of Medicine, University of Hawaii, Honolulu 96822.
Hemoglobin. 1988;12(5-6):539-50. doi: 10.3109/03630268808991643.
In screening families for alpha-thalassemia (thal) by the Southern blot technique, several Laotian families were found which had anomalous zeta-globin haplotypes. The zeta-globin genes encode alpha-like embryonic hemoglobin subunits in the alpha-globin multigene complex on chromosome 16. There are normally two zeta-globin genes in this cluster: 5' zeta 2 and 3' psi zeta 1. In our study, six individuals in three families had triple zeta-globin genes. Another family revealed a novel quadruple zeta-globin arrangement. Two aberrant fragments were seen in Eco R1, Bam H1, Bgl II and Hind III digests using a zeta-globin gene probe. These anomalous bands were in the integral 10 kb range consistent with duplication of the zeta-globin region. This haplotype interpretation was confirmed by Southern blot analyses using double digestions hybridized to a cDNA zeta-gene probe, and Pvu II digests probed with a 5'-psi zeta 1 intergenic fragment. Proposed mechanisms of recombination and implications of this novel arrangement are discussed.
在用Southern印迹技术对家庭进行α地中海贫血（地贫）筛查时，发现了几个老挝家庭存在异常的ζ珠蛋白单倍型。ζ珠蛋白基因在16号染色体上的α珠蛋白多基因复合体中编码类α胚胎血红蛋白亚基。该基因簇中通常有两个ζ珠蛋白基因：5'ζ2和3'ψζ1。在我们的研究中，三个家庭的六个人有三个ζ珠蛋白基因。另一个家庭显示出一种新的四个ζ珠蛋白的排列方式。使用ζ珠蛋白基因探针，在Eco R1、Bam H1、Bgl II和Hind III酶切中观察到两条异常片段。这些异常条带在完整的10 kb范围内，与ζ珠蛋白区域的重复一致。通过使用与cDNA ζ基因探针杂交的双酶切以及用5'-ψζ1基因间片段探针进行的Pvu II酶切的Southern印迹分析，证实了这种单倍型的解释。讨论了重组的可能机制以及这种新排列方式的意义。
