Related Experiment Video
Updated: Oct 15, 2026

Screening for Functional Non-coding Genetic Variants Using Electrophoretic Mobility Shift Assay (EMSA) and DNA-affinity Precipitation Assay (DAPA)
Published on: August 21, 2016
Identification of DNA variants in the SNAP-25 gene and linkage study of these polymorphisms and attention-deficit
1Department of Psychiatry, The Toronto Hospital, Western Division, Canada. CBarr@playfair.utoronto.ca
Abstract:
The gene for the synaptic vesicle docking fusion protein, synaptosomal-associated protein of 25 kDa (SNAP-25), has been implicated in the etiology of attention-deficit hyperactivity disorder (ADHD) based on the mouse mutant strain coloboma. This neutron-irradiation induced mouse strain is hemizygous for the deletion of the SNAP-25 gene and displays spontaneous hyperactivity that is responsive to dextroamphetamine. Because of these characteristics, this strain has been suggested to be a mouse model for ADHD. We identified using single stranded conformational polymorphism analysis (SSCP) four DNA sequence variants in the 3' untranslated region of the human SNAP-25 gene. We searched for polymorphisms in the 3' untranslated region because the intron/exon structure of this gene has not yet been determined. We tested for linkage of this gene and ADHD using two of the identified polymorphisms that change a restriction enzyme recognition site. We examined the transmission of the alleles of each of these polymorphisms and the haplotypes of both polymorphisms using the transmission disequilibrium test in a sample of 97 small nuclear families consisting of a proband with ADHD, their parents, and affected siblings. We observed biased transmission of the haplotypes of the alleles of these two polymorphisms. Our findings are suggestive of a role of this gene in ADHD.
Related Concept Videos
Attention-Deficit/Hyperactivity Disorder
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings.
Genome-wide Association Studies-GWAS
GWAS does not require the identification of the target gene involved in...
Comparing Copy Number Variations and SNPs
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Human Genetics
The complex relationship between genetics and psychology is observable through common biological components such...
Single Nucleotide Polymorphisms-SNPs
Behavioral Genetics and Its Designs
The primary methodologies used in behavior genetics include family studies, twin studies, and adoption studies, each providing unique...

