Genital asymmetry in men

This study examined genital asymmetry in a large sample of men. Theprobands were 6544 non-delinquent men who were interviewed by the KinseyInstitute for Research in Sex, Gender and Reproduction from 1938 to 1963.The measures were four indicators of penile and scrotal asymmetry, alongwith self-reported handedness, from Kinsey's interview protocol. Most menreported some degree of lateral asymmetry in their flaccid penis and intheir testicles; less asymmetry was reported for their erect penis. Theasymmetry typically occurred in the left direction, and this patternoccurred in both right- and nonright- handers. However, this 'leftward'pattern was significantly less pronounced in nonright-handers. The resultsare discussed in relation to previous findings of genital asymmetry in men,the possible relationship of genital asymmetry to functional cerebralasymmetry, and recent data suggesting genital asymmetry may predictpatterns of cognitive performance and genital/sexual organ cancers.