Mosaicism in von Hippel-Lindau disease (VHL): an additional difficulty to the diagnosis

SANSÓ G; VIEITES AM; NEUMANN H P H; BARONTINI M

Costa do Sauípe

Congreso; XXI REUNION DE LA SOCIEDAD LATINOAMERICANA DE ENDOCRINOLOGIA PEDIATRICA; 2010

SLEP

Mosaicism in von Hippel-Lindau disease (VHL): an additional difficulty to the diagnosis Sanso G, Vieites A, Neumann HPH, Barontini M Hospital de Niños Ricardo Gutierrez, University Mediacal Center Freiburg Germany Department of Nephrology   VHL is an inherited syndrome characterized by the development of tumors in kidneys, adrenal glands, CNS, retina, pancreas and epididymis. It is transmitted in an autosomal dominant manner.Tumor formation in the hereditary setting is associated with a loss of heterozygosity at the vhl locus.Objetive:to describe a possible mosaicism in a VHL patient´ father. A VHL patient (15y) without familiar history was studied. Molecular diagnosis was carried out in four members of the family in lymphocytes and/or tissue DNA by PCR followed by direct sequencing and MLPA. A germline heterozygous point mutation Arg161Term was detected in the patient while normal findings were found in the MLPA.The peripheral DNA of the other members of the family were normal.The father presented at 53years a cerebellar hemangioblastoma, died post surgery and renal cysts were discovered. His DNA was re-analyzed and a mutation-related peak barely visible was detected. Tumor DNA was studied and a heterozygous mutation Arg167Trp and a smaller peak related to Arg161Term were apparent. These results suggest a mosaicism in the father with a late onset disease.It is important to recognize mosaicisms since they may be a cause of failure in molecular diagnosis. It has also implications for patient follow-up and genetic counseling.