Fig. 1

Representation of allelic trend for the association of PCSK6 with handedness. A quantitative measure for relative hand skill (PegQ) is normally distributed in the population with a positive mean score. PegQ is derived from measurements taken with the peg-board task which assess the time taken by the subjects to move a row of pegs from one location to another with the left hand (L) and right hand (R) separately. From these data, PegQ is derived with the formula , where a negative score indicates relative higher skills with the left hand and a positive score indicates relative higher skills with the right hand. Carriers of the minor allele of rs11855415 tend to be more skilled with their right hand if they have dyslexia, while they tend to score around the mean of PegQ if they do not have dyslexia (general population sample)