Differential role of sodium channels SCN1A and SCN2A gene polymorphisms with epilepsy and multiple drug resistance in the north Indian population.
OBJECTIVE
To evaluate sodium channel genes as candidates for epilepsy susceptibility and their role in therapeutic efficacy, we screened coding single-nucleotide polymorphism of SCN1A p. Thr 1067 Ala or c.3184 A-->G (rs2298771) and SCN2A p.Arg19Lys or c.56 G-->A (rs17183814) in north Indian epilepsy patients.


METHODS
The genotyping was performed in 160 control subjects and 336 patients with epilepsy, of whom 117 were drug resistant and 219 were drug responsive. Therapeutic drug monitoring for phenytoin, carbamazepine, phenobarbital and valproate was also performed in 20% of the patients to confirm compliance.


RESULTS
AG genotype of SCN1A 3184 A-->G polymorphism was significantly higher and associated in epilepsy patients [P= 0.005; odds ratio (OR) 1.76, 95% confidence interval (CI) 1.19, 2.61], whereas A variant of SCN2A c.56 G-->A was associated with multiple drug resistance in north Indian patients with epilepsy (P= 0.03; OR 1.62, 95% CI 1.03, 2.56).


CONCLUSIONS
Overall, results indicate a differential role of genetic polymorphisms of sodium channels SCN1A and SCN2A in epilepsy susceptibility and drug response.
Lakhan
Ram
R
Departments of Genetics and Neurology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014, India.
Kumari
Ritu
R
Misra
Usha K
UK
Kalita
Jayanti
J
Pradhan
Sunil
S
Mittal
Balraj
B
D044466:Asian People; D018432:Drug Resistance, Multiple / Q000187:drug effects / Q000235:genetics*; D004827:Epilepsy / Q000188:drug therapy / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008297:Male; D010641:Phenotype; D011110:Polymorphism, Genetic; D012016:Reference Values; D015222:Sodium Channels / Q000187:drug effects / Q000235:genetics*; D055815:Young Adult
D015222:Sodium Channels
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