Nevertheless, DNA was submitted for sequencing of genes that typically cause NCL with onset in late infancy and a known pathogenic mutation (c.316dupC: p.Arg106ProfsX26) was found in homozygous form in CLN6. Subsequent ultrastructural analysis re-examination of the second skin biopsy by transmission electron microscopy showed distinct storage inclusions in sweat gland epithelium, endothelial cells and smooth muscle cells (Fig. 2). The gene discussed is CLN6; the disease is neuronal ceroid lipofuscinosis.