0091

PRENATAL GENETIC DIAGNOSIS OF PHENYLKETONURIA,

TEN YEARS RETROSPECTION

Yuan LF1, Wang T1, Wang SZ1, Zhao SM2, Sun NH2, Lo H-Y1

1 Institute of Basic Medical Sciences, CAMS & PUMC, Beijing, China

2 Peking Union Medical College Hospital, Beijing, China

 

Objective: Classical phenylketonuria (PKU) is a rather common inherited metabolic disorder caused by a deficiency of hepatic phenylalnine hydroxylase (PAH). The majority of untreated PKU patients are severe mental retarded. Low phenylalanie diet starts from birth can prevent mental retardation. But it is too difficult. Many parents are seeking for prenatal diagnosis. During past 40 years, we performed 40 prenatal diagnosis of PKU.

Method: More than 200 cases of classical PKU were diagnosed at PUMC Hospital. 40 pregnancies with high risk of classical PKU requested for prenatal diagnosis. To detect PAH gene mutations, PCR-ASO (allele-specific oligonucleotide), PCR-SSCP (single strand conformation polymorfism) and PCR-STR (short tandem repeat) were used. Chorionic villi and amniotic cells were processed for prenatal diagnosis.at 8-12 weeks & 4-5 months respectively.

Results: Among 40 pregnancies 26 fetus were predicted normal, 24 were confirmed after birth, except two pregnancies were ended. One was ended for spontaneous abortion and another one for gynaecologic complication. 16 fetus were predicted as having PKU, one was given birth and was confirmed as affected. The rest pregnancies were ended.

Conclusion: Molecular techniques can be used to do prenatal diagnosis in pregnancies with high risk of PKU.