Polymerase chain reaction-based search for two alpha-globin gene mutations in India

Area of Science:

• Genetics
• Molecular Biology
• Hematology

Background:

• Alpha-thalassemia is a common inherited blood disorder.
• Specific mutations in the alpha-globin gene can lead to severe clinical manifestations like Hb H disease.
• Accurate detection of these mutations is crucial for diagnosis and genetic counseling.

Purpose of the Study:

• To detect the alpha-globin polyadenylation (poly A) signal mutation (AATAAA>AATA- -) and the Hb Sun Prairie mutation [alpha 130(H13)Ala-->Pro, GCT>CCT (alpha2)].
• To investigate the prevalence of these mutations in Indian patients with alpha-thalassemia and beta-thal intermedia.

Main Methods:

• Utilized restriction site-dependent polymerase chain reaction (PCR)-based methodology.
• Screened 77 putative alpha-thalassemia patients and 13 beta-thal intermedia patients.

Main Results:

• The alpha-globin polyadenylation signal mutation was found in nine of 77 alpha-thalassemia patients and three of 13 beta-thal intermedia patients.
• Four of the nine alpha-thalassemia patients with the polyadenylation mutation were homozygotes.
• The Hb Sun Prairie mutation was confirmed in two alpha-thalassemia patients (one homozygote, one heterozygote).

Conclusions:

• The alpha-globin polyadenylation signal mutation is frequent in the Indian population and a significant cause of Hb H disease in the homozygous state.
• Restriction site-dependent PCR is an effective method for detecting these specific alpha-globin gene mutations.
• These findings contribute to understanding the genetic basis of thalassemia in the Indian subcontinent.