Woman with UV hypersensitivity and a de novo unbalanced chromosome translocation.

We report a Japanese woman with de novo 6p monosomy and 10q trisomy [46,XX,der(6)t(6;10)(p25.1;q25.2)] whose clinical manifestations resemble those of xeroderma pigmentosum (XP) and Cockayne syndrome (CS), known as premature aging syndromes. She had a history of easy sunburning and presented a number of freckles and hypopigmented spots on her face as those of XP. Magnetic resonance imaging and computed tomography scanning demonstrated intracranial abnormalities like those seen in CS. DNA repair studies using the patient's fibroblasts demonstrated hypersensitive responses to ultraviolet (UV). XP, CS, and UV-sensitive syndromes with photosensitivity disturbances have been known as DNA repair abnormalities. However, an association of 6p monosomy with these diseases has not been reported so far. Molecular analysis of the patient we described may contribute to the identification of novel DNA-repair-related gene(s) and/or to the senile mechanism.