The main drawback of this paper is that, as the carrier mother did not express the phenotype, the link between PLXND1 and MS or PMS remains unproven and our observation simply adds further weight to the body of circumstantial evidence linking MS and PMS to the 3q21-22 locus and, perhaps, the PLXND1 gene. Here, PLXND1 is linked to premenstrual tension.