Subcortical band heterotopia (SBH), also known as doublecortex syndrome, is a malformation of cortical development resulting from mutations in the doublecortin gene (DCX).
Neuroanatomical similarities between the Tuba1a mutant mouse and mice deficient for Doublecortin (Dcx) and Lis1 genes, and the well-established functional interaction between DCX and microtubules (MTs), led us to hypothesize that mutations in TUBA1A (TUBA3, previous symbol), the human homolog of Tuba1a, might give rise to cortical malformations.
In addition, 6 patients had no defined genetic defect, although the patient with subcortical band heterotopia exhibited the same pattern of malformation expected with an XLIS mutation.
We found consistent differences in the gyral patterns, with the malformation more severe posteriorly in individuals with LIS1 mutations and more severe anteriorly in individuals with XLIS mutations.