A comparative study for diagnostic value of normal fetal cardiac by transvaginal ultrasonography as compared with transabdominal approach / 中华医学超声杂志（电子版）

Objective To assess the value of ultrasound examination in transvaginal diagnosis of normal fetal heart with 11-14 weeks of gestation.Methods Totally 158 cases of normal fetal heart with high risk pregnancy and nuchal translucency thickness were examined by two ultrasoud approaches:transvaginal(TVS) and tranabdomina(TAS) in 11-14 weeks of gestation.Results The group of TVS was obviously clearer than TAS by displaying the normal fetal cardiac structural in 12 week of gestation and 13-14 weeks of gestation with significant difference between the two groups (P<0.05),respectively.No significant difference between the two groups in 11 week of gestation was observed.Conclusion The transvaginal echocardiogram is of clinical value in the high risk gravida during the late first and the early second trimester.

Prenatal diagnosis of 5 fetuses with high risk of developing spinal muscular atrophy / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To perform prenatal diagnosis for 5 pregnant women who had given birth to children with spinal muscular atrophy (SMA).</p><p><b>METHODS</b>Thirty to forty mililiters of amniotic fluid was obtained by amniocentesis under ultrasonic monitoring. DNA was extracted directly from sediment of amniotic fluid. Short tandem repeat (STR) profiling was carried out to evaluate the contamination of amniotic DNA by maternal genomic DNA. Two methods, PCR-restriction fragment length polymorphism (PCR-RFLP) and allele-specific PCR, were used to analyze exon 7 of SMN gene from amniotic DNA.</p><p><b>RESULTS</b>Comparing the 16 STR sites of each fetus with those of his/her parents, there was no or little contamination of amniotic DNA by maternal genomic DNA. In conventional PCR-RFLP, part of the PCR product (189 bp) from amniotic DNA of fetus A, C, or D remained intact after digestion with Dra I, while the PCR product from amniotic DNA of fetus B or E was completely digested by Dra I. In allele-specific PCR, exon 7 of both SMN1 and SMN2 gene could be seen when amniotic DNA of fetuses A, C, or D was analyzed, while only exon 7 of SMN2 could be seen when amniotic DNA of fetuses B or E was analyzed.</p><p><b>CONCLUSION</b>Homozygous deletion of SMN1 is not detected in fetuses A, C, and D, predicting that the risk of developing SMA after birth would be extremely low. Homozygous deletion of SMN1 was present in fetuses B and E suggesting high risk of developing SMA after birth.</p>

Prenatal molecular diagnosis of adrenoleukodystrophy / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To carry out prenatal diagnosis on two fetuses of different pedigrees with X-linked adrenoleukodystrophy (ALD).</p><p><b>METHODS</b>The amniotic fluid was obtained with the help of a clinical doctor and the genomic DNA was isolated from it. Maternal DNA contamination was excluded by fluorescent STR profiling, The R617G mutation found in the first pedigree was searched in genomic DNA of amniotic fluid cells (AFC) from fetus 1 by amplification refractory mutation system (ARMS) and dot DNA hybridization while the P534R mutation found in pedigree 2 was analyzed in the AFC genomic DNA of fetus 2 by restrictive digestion with Hae II and DNA direct sequencing.</p><p><b>RESULTS</b>A specific band (185 bp) was detected from the genomic DNA of the first fetus and his mother by using mutation primer in ARMS but not from that of the first fetus's father and unrelated controls. DNA dots were visualized only in the fetus 1 and carrier when using the mutation probe in DNA hybridization. In the other ALD family, the PCR product (506 bp) of the second fetus which spanned the site of P534R mutation could not be digested with Hae II and no mutation was detected in the ABCD1 gene from the genomic DNA of the fetus 2 by using DNA direct sequencing.</p><p><b>CONCLUSION</b>Fetus 1 had R617G mutation on his ABCD1 gene and he was an adrenoleukodystrophy hemizygote. Fetus 2 had no P534R mutation on his ABCD1 gene and he was a normal hemizygote.</p>