Prenatal Diagnosis of Placental Mesenchymal Dysplasia with 46, X, Isochromosome Xq/45, X Mosaicism.

Placental mesenchymal dysplasia is an uncommon vascular anomaly of the placenta with characteristics of placentomegaly and multicystic appearance and with or without association with fetal chromosomal anomaly. We present a unique placental mesenchymal dysplasia patient with amniotic fluid karyotyping as 46, X, iso(X) (q10). Detailed molecular testing of the amniotic fluid, fetal cord blood, non-dysplastic placenta and dysplastic placenta was conducted after termination of pregnancy, from which we proved biparental/androgenetic (46, X, i(X) (q10)/45, X) mosaicism in different gestational tissues. A high portion of androgenetic cells in dysplastic placenta (74.2%) and near 100% of biparental cells in the fetus's blood and amniotic fluid were revealed. Delicate mosaic analyses were performed, and possible pathogenesis and embryogenesis of this case were drawn up.

Adverse Perinatal and Early Life Outcomes following 15q11.2 CNV Diagnosis.

The copy number variation (CNV) of 15q11.2, an emerging and common condition observed during prenatal counseling, is encompassed by four highly conserved and non-imprinted genes-TUBGCP5, CYFIP1, NIPA1, and NIPA2-which are reportedly related to developmental delays or general behavioral problems. We retrospectively analyzed 1337 samples from genetic amniocentesis for fetal CNV using microarray-based comparative genomic hybridization analysis between January 2014 and December 2019. 15q11.2 CNV showed a prevalence of 1.5% (21/1337). Separately, 0.7% was noted for 15q11.2 BP1-BP2 microdeletion and 0.8% for 15q11.2 microduplication. Compared to the normal array group, the 15q11.2 BP1-BP2 microdeletion group had more cases of neonatal intensive care unit transfer, an Apgar score of <7 at 1 min, and neonatal death. Additionally, the group was symptomatic with developmental delays and had more infantile deaths related to congenital heart disease (CHD). Our study makes a novel contribution to the literature by exploring the differences in the adverse perinatal outcomes and early life conditions between the 15q11.2 CNV and normal array groups. Parent-origin gender-based differences may help in the prognosis of the fetal phenotype; development levels should be followed up in the long term and echocardiography should be offered prenatally and postnatally for the prevention of a delayed diagnosis of CHD.

Prenatally diagnosed de novo segmental amplification or deletion by microarray-based comparative genomic hybridization: A retrospective study.

OBJECTIVE: Prenatal diagnosis of de novo segmental amplification or deletion by microarray-based comparative genomic hybridization (array CGH) is uncommon. The study aimed to know about the incidence, abnormal ultrasound findings, and pregnancy outcomes of prenatally diagnosed de novo segmental amplification or deletion by array CGH. MATERIALS AND METHODS: Between January 2014 and December 2017, we analyzed pregnant women who received prenatal array CGH (SurePrint G3 Human CGH Microarray Kit, 8 × 60K) at Chang Gung Memorial Hospital, Taiwan. Clinical data on maternal age, reason for fetal karyotyping, sonographic findings, gestational age at delivery, newborn birth weight, and associated anomalies, if any, were obtained by chart review. RESULTS: A total of 836 specimens (814 amniotic fluid samples, 4 cord blood samples, 18 chorionic villi samples) were analyzed by array CGH during the study period. Of the 56 cases with abnormal array CGH results, 40 had segmental amplification or deletion, 12 had trisomy, three had monosomy, and one had sex chromosome aneuploidy. Of these 40 cases with segmental amplification or deletion, 30 were inherited and 10 were de novo occurrences. The incidence of de novo segmental amplification or deletion was 1.2% (10/836). Abnormal prenatal ultrasound findings occurred in 40% (4/10) of de novo segmental amplification or deletion cases. Among these 10 pregnancies, nine were voluntarily terminated between 22 and 26 weeks of gestation and one was delivered at term. CONCLUSIONS: Prenatal diagnosis of de novo segmental amplification or deletion by array CGH raises important genetic counseling issues. In our series, the incidence of de novo segmental amplification or deletion in prenatal samples was 1.2%. Abnormal prenatal sonographic findings occurred in 40% of these de novo segmental amplification or deletion cases. Of these de novo segmental amplification or deletion pregnancies, 90% were voluntarily terminated.

Antioxidant deficit and enhanced susceptibility to oxidative damage in individuals with different forms of alpha-thalassaemia.

alpha-Thalassaemia is a common red cell disorder in Taiwan, affecting 6-8% of Taiwanese. Previous studies have shown that reactive oxygen species are generated in increased amounts in thalassaemic red cells. This implies the possible alteration of redox status in thalassaemic patients, which may adversely affect their health. In the present study, the redox status of patients with alpha-thalassaemia trait and haemoglobin H (Hb H) disease was investigated. Lipid peroxidation, as measured by the level of plasma thiobarbituric acid reactive substances (TBARS), was increased in alpha-thalassaemic patients, with the highest level of TBARS in Hb H disease patient. The plasma levels of vitamin A, C, and E were significantly lower in alpha-thalassaemic patients than in controls. The overall antioxidant capacity in plasma was inversely correlated with the severity of alpha-globin gene defect: the more severe the form of alpha-thalassaemia, the lower the overall antioxidant capacity in plasma. Erythrocytes isolated from alpha-thalassaemia patients had lower levels of vitamin E, glutathione, catalase and superoxide dismutase. In addition, these alpha-thalassaemic red cells were more susceptible to hydrogen peroxide-induced lipid peroxidation and decrease in deformability. All these data suggest that the alpha-thalassaemic patients suffer from increased oxidative stress and antioxidant deficit, which may complicate the pathophysiology of alpha-thalassaemia.

Prenatal diagnosis of alpha-thalassemia of Southeast Asian deletion with non-radioactive southern hybridization.

BACKGROUND: Alpha-thalassemia is a common hereditary disease in Taiwan. Affected patients always carry a heavy burden of morbidity and early death. Prenatal diagnosis has reduced the disease burden on families and the health care system. This study evaluated a new non-radioactive Southern blotting hybridization method for prenatal diagnosis of this disease. METHODS: Seventy two chorionic villi samples (CVS) and 30 amniocyte samples from 102 pregnancies of couples who were both heterozygous for alpha-thalassemia-1 of the Southeast Asian (SEA) type deletion were studied. A non-radioactive Southern blotting hybridization method using a dig-alkaline phosphate detection system was developed for use in this study. RESULTS: Non-radioactive Southern blotting hybridization data showed that 19 (26%) CVS and five (17%) amniotic fluid samples had 10 Kb and 4Kb fragments, indicating homozygosity of the alpha-thalassemia-1 SEA type deletion. DNA samples were extracted from most of the aborted tissue of the 24 fetuses with a diagnosis of homozygous for the alpha-thalassemia-1 SEA type deletion. Homozygosity for alpha-thalassemia-1 SEA type deletion was reconfirmed by Southern blotting hybridization in all of these samples. CONCLUSIONS: The non-radioactive Southern hybridization protocol used in this study allows efficient and accurate early prenatal diagnosis of alpha-thalassemia-1 SEA type deletion. It can be routinely used for testing couples who both carry the alpha-thalassemia-1 SEA type deletion.