9 research outputs found
Prader-Willi syndrome: Methylation study or fluorescence in situ hybridization first?
Prader-Willi syndrome (PWS) is neurogenetic disorder involving the
imprinting mechanism at 15q11-13 region. We report a 4-year-old girl
who was referred to our laboratory to be investigated for clinical
obesity, mental deficiency and respiratory problems. The patient was
born for non-consanguineous and healthy biological parents. After
normal pregnancy, the patient was delivered by cesarean section at full
term, with a birth weight of 2500 g, and the height and head
circumference were unknown. In neonatal stage, she presented severe
hypotonia with feeding problems. Her developmental progress was
delayed. She walked and developed speech at the age of 3 years. Since
the age of 3 years, she presented severe dental problems. Methylation
study had confirmed the diagnosis, and for detecting etiology,
fluorescence in situ hybridization using probes for small nuclear
ribonucleoprotein polypeptide N (SNRPN), which map inside the
chromosomal region 15q11-15q13, was necessary to confirm the
15q11-15q13 deletion of paternal chromosome 15, which is the
predominant genetic defect in PWS. In conclusion, we report this case
with an objective to reinforce the necessity of analysis of DNA
methylation within the 15q11-13 region, which is an important tool for
the correct diagnosis among children presenting with neonatal
hypotonia, mental deficiency and obesity