Gwo-Chin Ma

A recurrent ITGA9 missense mutation in human fetuses with severe chylothorax: possible correlation with poor response to fetal therapy

To assess the possible correlations between the reported candidate genes (VEGFR3, FOXC2, ITGA9 and ITGB1) and the clinical response in fetuses with severe congenital chylothorax (CC) treated by prenatal OK‐432 pleurodesis.

Experimental treatment of bilateral fetal chylothorax using in‐utero pleurodesis

To assess the use and efficacy of in‐utero pleurodesis for experimental treatment of bilateral fetal chylothorax.

The spectrum of the factor 8 (F8) defects in Taiwanese patients with haemophilia A.

Summary.  Haemophilia A (HA) is an X‐linked recessive bleeding disorder caused by various types of pathological defects in the factor VIII gene (F8), which encodes coagulation factor VIII (FVIII). To date, several studies on the spectra of F8 defects have been performed in Western populations, but similar studies in Asian races are scarce. Here, we report the distribution of the mutations within the F8 gene in 31 Taiwanese unrelated HA patients (19 severe and 10 moderate/mild males and two severe females). Of these, 12 (38.7%) and one (3.2%) severe males were genotyped with the recurrent IVS22 and IVS1 inversion, respectively, similar to that in general populations (IVS22: 40–50%; IVS1: 2–5%). The F8 defects in the remaining 18 inversion‐negative patients cover a wide spectrum, in which 17 different mutations were identified (10 missense and three nonsense mutations, and two small and two large deletions). Eleven of these mutations are novel: seven caused missense substitutions and four resulted in truncated proteins. To assess the putative pathogenetic impacts of the newly amino acid substitutions, computer analyses were performed based on molecular 3D modelling. The degree of conservation in cross‐species FVIIIs and the position in known functional FVIII regions were studied. The novel missense mutations found in our series all occurred at evolutionary conserved residues that may carry a functional importance in our analyses. The results of this study add the short list of Taiwanese/Chinese F8 mutations, and will enhance our understanding of the molecular basis of FVIII function and the mechanism underlying HA.

Genome‐wide normalized score: a novel algorithm to detect fetal trisomy 21 during non‐invasive prenatal testing

Non‐invasive prenatal testing for fetal trisomy 21 (T21) by massively parallel shotgun sequencing (MPSS) is available for clinical use but its efficacy is limited by several factors, e.g. the proportion of cell‐free fetal DNA in maternal plasma and sequencing depth. Existing algorithms discard DNA reads from the chromosomes for which testing is not being performed (i.e. those other than chromosome 21) and are thus more susceptible to diluted fetal DNA and limited sequencing depth. We aimed to describe and evaluate a novel algorithm for aneuploidy detection (genome‐wide normalized score (GWNS)), which normalizes read counts by the proportions of DNA fragments from chromosome 21 in normal controls.

Complex Rearrangements Between Chromosomes 6, 10, and 11 With Multiple Deletions at Breakpoints

Here we report on a girl with minor facial anomalies, cleft palate, seizures, microcephaly, psychomotor retardation, and a congenital heart defect. Complex of cytogenetic methods [GTG‐banding, spectral karyotyping (SKY), fluorescence in situ hybridization (FISH), multicolor banding (mBAND), and comparative genomic hybridization (array CGH)] showed complex chromosomal rearrangements (CCRs) involving chromosomes 6, 10, and 11 and 4 deletions at the breakpoints. Her father had an unrelated translocation between chromosomes 3 and 16, suggesting the possibility of an autosomal dominant trait that predisposes to complex synapses and recombination between multiple chromosomes during meiosis. This study demonstrates the power of combining available chromosome analysis technologies in resolving CCR.

Number of somatic mutations in the mitochondrial D-loop region indicates poor prognosis in breast cancer, independent of TP53 mutation

The objective of this study was to investigate whether somatic mutations in the mitochondrial DNA (mtDNA) D-loop region correlate with known prognostic factors, namely, age, tumor size, lymph node status, metastasis, tumor-node-metastasis stage, lymphovascular invasion, and status of the progesterone receptor, estrogen receptor, ERBB2 (alias HER2/neu), and TP53 proteins (as determined by immunohistochemistry) and to investigate their relationship, if any, to TP53 mutations in human breast cancer. Thirty breast tumors without BRCA mutation, along with adjacent nontumorous tissues, were genotyped for the mtDNA D-loop region and for the promoter as well as the coding region of the TP53 gene. Clinicopathological parameters were recorded and assessed. In all, 17 somatic mtDNA D-loop mutations were identified, in 13 of 30 tumor samples (43%); two mutations were novel: 544C>T and 16510A>C. Four TP53 mutations were found in six tumor samples (20%), and two (c.437G>A and c.706T>C) were novel. Only progesterone receptor status correlated with the number of somatic mtDNA D-loop mutations (likelihood chi-square test; P < 0.05). Somatic mutations in the mtDNA D-loop and in TP53 were independent of each other (Fishers exact test; P > 0.05). These results suggest that the number of somatic mtDNA D-loop mutations may be an indicator of poor prognosis through a mechanism independent of TP53.

A case of restrictive dermopathy with complete chorioamniotic membrane separation caused by a novel homozygous nonsense mutation in the ZMPSTE24 gene.

A Case of Restrictive Dermopathy With Complete Chorioamniotic Membrane Separation Caused by a Novel Homozygous Nonsense Mutation in the ZMPSTE24 Gene Ming Chen, Hsiang-Hsu Kuo, Yi-Chen Huang, Yu-Yuan Ke, Shun-Ping Chang, Chih-Ping Chen, Dong-Jay Lee, Meng-Luen Lee, Mei-Hui Lee, Tze-Ho Chen, Chia-Hsiang Chen, Hui-Mei Lin, Chin-San Liu, and Gwo-Chin Ma* Department of Genomic Medicine, Changhua Christian Hospital, Changhua, Taiwan Department of Medical Research, Changhua Christian Hospital, Changhua, Taiwan Department of Obstetrics and Gynecology, Changhua Christian Hospital, Changhua, Taiwan Department of Obstetrics and Gynecology, National Taiwan University Hospital, Taipei, Taiwan Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan Department of Obstetrics and Gynecology, Puli Christian Hospital, Nantou, Taiwan Department of Pediatrics, Puli Christian Hospital, Nantou, Taiwan Department of Pediatrics, Changhua Christian Hospital, Changhua, Taiwan Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan Department of Neurology, Vascular Biology and Genomics Center, Changhua Christian Hospital, Changhua, Taiwan Institute of Biochemistry and Biotechnology, Chung-Shan Medical University, Taichung, Taiwan

Microdeletions/duplications involving TBX1 gene in fetuses with conotruncal heart defects which are negative for 22q11.2 deletion on fluorescence in-situ hybridization

Conotruncal heart defects (CTD) are associated with del22q11.2 syndrome, which is often diagnosed by fluorescence in‐situ hybridization (FISH). However, in those negative for del22q11.2 on FISH, the etiology is usually obscure. We aimed to use high‐resolution array comparative genomic hybridization (array CGH) to clarify the underlying genetic causes in these cases.

Molecular delineation of the Y-borne Sry gene in the Formosan pangolin (Manis pentadactyla pentadactyla) and its phylogenetic implications for Pholidota in extant mammals

The systematic status of Pholidota has been a matter of debate, particularly regarding the apparent inconsistency between morphological and molecular studies. The Sry gene, a master regulator of male sex determination in eutherian mammals, has not yet been used for phylogenetic analyses of extant mammals. The objective of the present study was to clone and characterize the complete gene (1300 base pairs; bp) and amino acid sequences (229 residues) of Sry from the Formosan pangolin (Manis pentadactyla pentadactyla), a member of Pholidota. The Sry amino acid identity between pangolin and other reported species ranged from 42.5% (mouse, Mus musculus) to 84.1% (European hare, Lepus europaeus). Sequence conservation was primarily in the high motility group (HMG) box (234 bp), whereas homology outside the HMG box was low. The cloned Sry was mapped to the pangolin Y chromosome by fluorescence in situ hybridization (FISH); this was confirmed to be the first Y-borne molecular marker identified in Pholidota. Based on Bayesian phylogenetic analysis for Sry HMG sequences from 36 representative taxa, including the Formosan pangolin, Pholidota was more closely related to Carnivora than to Xenarthra, consistent with the emerging molecular tree inferred from markers not located on the Y chromosome. In conclusion, this study characterized the gene structure of Sry of the Formosan pangolin and provided insights into the phylogenetic position of Pholidota.

Preimplantation and prenatal genetic diagnosis of aromatic L-amino acid decarboxylase deficiency with an amplification refractory mutation system-quantitative polymerase chain reaction

OBJECTIVES To develop a diagnostic platform for preimplantation genetic diagnosis (PGD) and prenatal genetic diagnosis (PND) to prevent births of aromatic L-amino acid decarboxylase deficiency (AADC) patients. MATERIALS AND METHODS Five Taiwanese families carrying AADC were enrolled. A novel technique, amplification refractory mutation system-quantitative polymerase chain reaction (ARMS-qPCR), was developed for both of PGD and PND. For PGD, blastomere biopsies of day-3 cleavage-stage embryos were subjected to ARMS-qPCR. Villi, cultured amniocytes, or both were used to confirm the PGD result; this approach could also be used as the sole method for PND after in vivo conception). RESULTS Unaffected live births were achieved in four of the five families, except one with ongoing PGD. The ARMS-qPCR correctly classified blastomeres (from day-3 cleavage-stage embryos) as affected (homozygous mutant), carrier (heterozygous for mutant and wild-type alleles), or normal (homozygous wild-type) within 1 working day. CONCLUSIONS To our knowledge, this is the first report of successful PGD of AADC. The molecular technique we devised (ARMS-qPCR) was applicable for PGD as well as PND of AADC. Furthermore, it has great potential for similar applications in other monogenic disorders.