Association between serotonin 2C gene polymorphisms and attention deficit hyperactivity disorder comorbid or not comorbid with learning disorder / 北京大学学报(医学版)

ABSTRACT

Objective: To investigate the relationship between two HTR2C gene polymorphisms, that is C 759T and G 697C polymorphisms, and attention deficit hyperactivity disorder (ADHD) comorbid or not comorbid learning disorder (LD). Methods: Blood samples were taken from 189 trios with probands of ADHD comrbid LD (ADHD+LD) and 299 trios with probands of ADHD not comorbid LD (ADHD-LD). DNA was extracted and PCR was performed to amplify the fragments containing both C 759T and G 697C polymorphisms. Aci Ⅰ was used to detect different alleles of the two polymorphisms. Allele based and haplotype based TDT analysis were used to test the association of the two polymorphisms of HTR2C gene and ADHD-LD and ADHD+LD. Results: 759C(? 2= 6.961 , P =0.008), 697G(? 2=8.346, P =0.004), as well as 759C/ 697G haplotype were over transmitted(? 2=9.000, P = 0.002 7), while haplotype 759T/ 697C was under transmitted(? 2= 7.784 , P =0.005 3) to probands with ADHD-LD. No biased transmission of any allele and haplotype were found in families with probands of ADHD+LD. Conclusion: ADHD-LD and ADHD+LD are different at the level of HTR2C gene polymrohisms of C 759T and G 697C. HTR2C is related to ADHD-LD, while not related to ADHD+LD.