Impact of molecular mechanisms, including deletion size, on Prader-Willi syndrome phenotype: study of 75 patients

Autor(es)

Varela, Monica Castro ^[1] ; Kok, Fernando ; Setian, N. ; Koiffmann, Celia Priszkulnik

Afiliação do(s) autor(es)

^[1] Universidade de São Paulo (USP). Instituto de Biociências. Departamento de Genética e Biologia Evolutiva - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Clinical Genetics; v. 67, n. 1, p. 47-52, Jan. 2005.
• Área do conhecimento: Ciências Biológicas - Genética
• Assunto(s): Genética médica Síndrome de Prader-Willi Fenótipo

Resumo

Prader-Willi syndrome (PWS) can result from a 15q11-q13 paternal deletion, maternal uniparental disomy (UPD), or imprinting mutations. We describe here the phenotypic variability detected in 51 patients with different types of deletions and 24 patients with UPD. Although no statistically significant differences could be demonstrated between the two main types of PWS deletion patients, it was observed that type I (BP1-BP3) patients acquired speech later than type II (BP2-BP3) patients. Comparing the clinical pictures of our patients with UPD with those with deletions, we found that UPD children presented with lower birth length and started walking earlier and deletion patients presented with a much higher incidence of seizures than UPD patients. In addition, the mean maternal age in the UPD group was higher than in the deletion group. No statistically significant differences could be demonstrated between the deletion and the UPD group with respect to any of the major features of PWS. In conclusion, our study did not detect significant phenotypic differences among type I and type II PWS deletion patients, but it did demonstrate that seizures were six times more common in patients with a deletion than in those with UPD. (AU)

• Processo FAPESP: 99/10414-8 - Caracterizacao dos pontos de quebra em pacientes com delecao ou duplicacao do segmento 15q11 - q13 e suas consequencias fenotipicas.
• Beneficiário: Monica Castro Varela Rodrigues da Silva
• Modalidade de apoio: Bolsas no Brasil - Doutorado