Prothrombin G20210A polymorphism in patients with venous and cryptogenic arterial strokes among ethnic groups in south and north India.

Background. Prothrombin (PT) G20210A is one of the genetic polymorphisms associated with thrombophilia. Studies show a low prevalence for this polymorphism in Asian populations with only one subject reported from India. We studied the prevalence and association of this polymorphism in patients with arterial and venous strokes and their matched controls in south and north India. Methods. We recruited patients with cerebral venous thrombosis (mean age 37.2 years) and cryptogenic ischaemic stroke (mean age 36.7 years), and age- and sex-matched controls (mean age 37.6 years) from south and north India. Genotyping was carried out using polymerase chain reaction followed by restriction fragment length polymorphism, and the prevalence of the variants among the patients and controls was compared. Results. The heterozygous allele of the polymorphism was detected in both groups with significantly higher prevalence among north Indians (5/154; 3.2%) compared with south Indians (4/516; 0.8%; p = 0.026). Thrombosis as a manifestation of this polymorphism was more among north Indians with 4/82 (4.9%) of patients with ischaemic stroke and cerebral venous thrombosis having this polymorphism compared with south Indian patients 1/72 (1.4%), p =0.003. Conclusion. PT G20210A is prevalent in India, especially among those from north India. Its role in predisposition to thrombosis needs to be studied further along with other known risk factors.