Non-balanced translocation between the short arms of chromosomes 8 and 6 associated with type 1 diabetes mellitus.

Patients with an unbalanced translocation between the short arms of chromosomes 6 and 8 - 46,XX,add(8)(p23).ish der(8)t(6;8)(GS-196I5+;RP-11338B22-) may present syndromic features suggestive of chromosome 8 trisomy. Main characteristics are a prominent forehead, ocular and breast hypertelorism, ocular, external ear and palate abnormalities, a short neck, heart defects, and developmental delay. Patients with 46,XX,add(8)(p23).ish der(8)t(6;8)(GS-196I5+;RP-11338B22-) may present autoimmune type 1 diabetes mellitus. Karyotyping is an essential tool for the diagnosis of chromosomal changes, but it has some limitations. Multiplex ligation-dependent probe amplification, array-single nucleotide polymorphism and fluorescence in situ hybridization can help diagnose genetic syndromes in patients with atypical evolution.