Reacción a "Reactions to study linking rare genetic variants with left-handedness"

In the European population the percentage of left-handedness is around 10 % of the population. Researchers have tried to find a gene involved in this trait. After analysing and comparing the coding regions of more than 38,000 left-handed and more than 300,000 right-handed people in the UK biobank, they were only able to detect very rare genetic variants in heterozygosity in one gene, TUBB4, in less than 29 left-handed people (i.e. in less than one per thousand left-handed individuals). These identified variants have not been found in right-handed people, although similar variants in the same gene have been found in 89 right-handed people.  

Although the sequencing and analysis work is correct, the interpretation of the results seems to me to be overestimated. The statistical predictive value, with these very, very low numbers, is irrelevant, as it cannot be shown that this gene is a determinant for this trait, particularly considering that left-handedness is very common in the population. I don't think it can be concluded that the gene for left-handedness has been found.