Megalencephalic Leukoencephalopathy with Subcortical Cysts (MLC) is a rare autosomal recessive disease presenting with increased head circumference at birth or in early infancy. MLC1 (MIM 605908) mutations are responsible for this disorder. In this study, we sequenced the entire coding region of the MLC1 gene in 13 patients and detected five novel nucleotide variations in six of them. Two of the novel variations created a missense amino acid change and the other three were located in the introns and were putative splice mutations. One novel missense variation was observed in two unrelated patients from the central Black Sea region, and the data suggested a founder haplotype for this novel variation. Similarly, three unrelated patients with the previously reported p.Thr118Arg mutation shared a common haplotype. These data suggest an Anatolian origin for these two mutations. As in the previous reports, it is not possible to correlate the clinical phenotype of the patients with the mutation spectra. (C) 2010 Elsevier Masson SAS. All rights reserved.