Glenn W Knox
Genetic Factors in Vestibular Function and Motion Sickness
Objectives: To determine if motion sickness has a genetic basis, and, if so, to determine if there is a correlation between motion sickness genetic factors and genetic factors governing vestibular function.
Data sources: The scope of review in this paper includes studies involving collection of primary data on susceptibility to motion sickness, correlated with any genetic factor; and, review articles concerning vestibular function and genetic factors.
Study selection: A literature review was conducted to obtain articles that pertained to genetic factors governing vestibular function. To locate articles, sources including PubMed were utilized to locate review articles with the key words genetic,vestibular and motion sickness.
Data extraction: Requirement that articles are written in English and published in the past 25 years.
Data synthesis: Direct correlation.
Conclusions: The selected articles revealed that: (1) Genetic polymorphism of the alpha-2a adrenergic receptor is correlated with motion sickness susceptibility in that the 6.3 Kb gene is correlated with increased susceptibility to motion sickness as compared to the 6.7 Kb polymorph; and (2) There is a lack of significant genetic correlation between the gene for the alpha-2a adrenergic receptor and genetic factors governing vestibular function. This data is in agreement with the observation that individuals who are highly susceptible to motion sickness tend to have normal vestibular function. In other words, subjects with a lack of peripheral vestibular function are generally resistant to motion sickness.