Associations between chronotype, road accidents and polymorphisms in genes linked with biological clock and dopaminergic system

Abstract

Public transport driving is a highly demanding activity requiring high skills and responsibility. Shift work, problems with regular sleep schedule negatively impact psychomotor reactions, cognitive functions and ability to react appropriately to the changing environment. For professional drivers all these factors may lead to the increased risk of a road accident. Individual differences in chronotype, cognitive and emotional control are partially genetically determined. Objective. Our study aimed to investigate the possible associations between chronotype parameters, traffic accident history and single nucleotide polymorphisms (SNPs) in a number of genes: RORA (rs1159814), CLOCK (rs12649507), PER3 (rs2640909), NPSR1 (rs324981), NPAS2 (rs4851377), DRD3 (rs6280), SLC6A3 (rs6347), DBH (rs1611125). Methods. We have studied 303 professional bus drivers working on rolling shifts in the Moscow region who had a recorded history of road accidents. The studied group was genotyped on selected SNPs and has filled out two chronotype questionnaires: MCTQ and shortened SWPAQ (Putilov A.A, 2014). Results. A mixed chronotype with high levels of morning and evening alertness prevailed in the group. A prominent social jetlag caused by shift work was found. For SNP in PER3 gene there was an association with morning activation. SNP in CLOCK gene was associated with social jetlag and the risk to cause a crash. Minor alleles of SNPs in NPSR1and SLC6A3 correlated with later chronotype and increased risk of a road accident. We suppose that these polymorphisms may be amongst the genetic factors connecting chronotype and road accident risk.