research Evaluation of the Predictive Capacity of DNA Variants Associated with Straight Hair in Europeans 36 citations , September 2015 in “Forensic Science International: Genetics” Certain DNA variants can predict straight hair in Europeans but are not highly specific.
research Common Variants in the Trichohyalin Gene Are Associated with Straight Hair in Europeans 234 citations , November 2009 in “American journal of human genetics” Common variants in the Trichohyalin gene are linked to straight hair in Europeans.