Dong-Jay Lee

Comparison of Immunohistochemical and Fluorescence In Situ Hybridization Assessment for HER-2/neu Status in Taiwanese Breast Cancer Patients

OBJECTIVE Accurate diagnostic assessment of human epidermal growth factor receptor-2 (HER-2) is essential and a prerequisite for appropriate application of the humanized anti-HER-2 monoclonal antibody trastuzumab (Herceptin) to the treatment of patients with breast cancer. Immunohistochemistry (IHC) is the most widely applicable diagnostic modality in studying HER-2 status. Fluorescence in situ hybridization (FISH) is also recognized as a modality in cases with an equivocal IHC status (score, 2+). Some authors claimed that FISH alone is sufficient. The aim of this study was to correlate the test results of IHC and FISH for HER-2 gene amplification in breast cancer patients. FISH for topoisomerase IIalpha (TOP2A) was also studied to see if deletion or amplification of TOP2A has any supplementary role to HER-2, FISH and IHC. MATERIALS AND METHODS Assessment of HER-2 gene amplification and TOP2A gene amplification/deletion was made by FISH analysis using the LSI TOP2A/HER-2/CEP 17 multicolor probe or the LSI HER-2/CEP dual color probe (Vysis, Downers Grove, IL, USA) in formalin-fixed and paraffin-embedded tissue sections of 54 breast cancer patients who were grouped into stages 1+, 2+ or 3+ based on IHC (HercepTest; DakoCytomation, Carpinteria, CA, USA) observations. RESULTS None of IHC 1+ breast tumors was HER-2 FISH positive, but three of 18 (17%) IHC 3+ tumors were HER-2 FISH negative. Overall, 53% of the IHC 2+ and 83% of the IHC 3+ cases were HER-2 FISH positive. Only one case with IHC 3+ tumor that was HER-2 FISH positive was found to have TOP2A amplification (>2.0) and no IHC 2+ cases were found to have TOP2A amplification. There were no cases with TOP2A deletion (<0.8) in our whole series. There were also no cases of HER-2 FISH negative tumors, but IHC scored as 2+ or 3+ (0 of 10), to be found with TOP2A amplification. The discordance rates by IHC were high (46.7% in IHC 2+, 16.7% in IHC 3+, 30.3% overall in IHC 2+ or 3+). On the contrary, the discordance rates were zero if by FISH. CONCLUSION The current algorithm to use HER-2 FISH as a supplementary role to IHC HercepTest 2+ may need some modifications according to the local setting. TOP2A FISH adds little value to HER-2 FISH and IHC staining in our study.

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.

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.

Subtelomeric rearrangements and 22q11.2 deletion syndrome in anomalous growth-restricted fetuses with normal or balanced G-banded karyotype.

To determine the frequencies of cryptic subtelomeric rearrangements and 22q11.2 deletion in anomalous growth‐restricted fetuses with normal or balanced G‐banded karyotypes.

A compound heterozygous GNPTAB mutation causes mucolipidosis II with marked hair color change in a Han Chinese baby

A Compound Heterozygous GNPTAB Mutation Causes Mucolipidosis II With Marked Hair Color Change in a Han Chinese Baby Gwo-Chin Ma, Yu-Yuan Ke, Shun-Ping Chang, Dong-Jay Lee, and Ming Chen* Department of Genomic Medicine, Changhua Christian Hospital, Changhua, Taiwan Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan Department of Pediatrics, Changhua Christian Hospital, Changhua, Taiwan Department of Obstetrics and Gynecology, National Taiwan University, Taipei, Taiwan Department of Life Sciences, National Chung-Hsing University, Taichung, Taiwan Department of Life Sciences, Tunghai University, Taichung, Taiwan

Use of a cytogenetic whole-genome comparison to resolve phylogenetic relationships among three species: implications for mammalian systematics and conservation biology.

The objective was to apply a novel modification of a genome-wide, comparative cytogenetic technique (comparative genomic hybridization, comparative genomic hybridization (CGH)), to study species belonging to the myrmecophagous (ant/termite eating) mammalian orders/superorders (Pholidota, Tubulidentata, Carnivora, and Xenarthra), as a model for other applications in mammalian systematics and conservation biology. In this study, CGH was applied to high-quality metaphase spreads of pangolin (Pholidota), using probes of sloth and canine (Xenarthra and Carnivora, respectively) genomic DNA labeled with different fluorophores, thereby facilitating analysis of the visible color spectrum on pangolin karyotypes. Our results posited that pholidotes are closer to carnivores than to xenarthrans, which confirmed the current consensus that myrmecophagy in these mammalian lineages was more likely because of homoplasy (convergent evolution) than being an ancestral character. Since the modified CGH technique used is genome-wide, has chromosome-level resolution, and does not need full genome sequencing, it has considerable potential in systematics and other fields.

Prenatal transient alveolomaxillary defect in a case of mucolipidosis II (I‐cell disease)

Mucolipidosis II (ML II or I-cell disease) is a rare inherited lysosomal storage disease that causes multisystem deterioration and death in early childhood. Little is known about the fetal features of this condition, and therefore the diagnosis is usually established postnatally when core symptoms occur, including severe growth/developmental delay, coarse facial features, multiplex skeletal deformities and joint limitation1. We report a case of ML II which presented an uncommon fetal sign of transient alveolomaxillary defect (TAD) on prenatal ultrasound imaging before 28 weeks’ gestation. A 23-year-old Taiwanese primigravida was referred to our clinic for evaluation of fetal cleft lip/palate suspected on ultrasound examination at 24 weeks’ gestation. Detailed sonographic examination confirmed the presence of an alveolomaxillary defect, in which a hole in the maxilla was identified but the soft tissue of the upper lip appeared intact (Figure 1). No other associated structural abnormality was noted. Chromosome analysis revealed a normal male karyotype. The mother denied any drug or teratogen exposure and the personal and family histories of both parents were unremarkable. The pregnancy was then followed with normal serial ultrasound examinations. Unexpectedly, the alveolomaxillary defect

Interstitial Deletion 13q31 Associated with Normal Phenotype: Cytogenetic Study of a Family with Concomitant Segregation of Reciprocal Translocation and Interstitial Deletion

Gain or loss of a fragment in human chromosomes has been associated with abnormal phenotypes in numerous genetic disorders. However, it is also possible that lack or excess of a particular chromosomal segment is a neutral polymorphism among populations and thus does not cause obvious abnormal phenotype. In this study, conventional GTG-banded karyotyping and molecular cytogenetic analyses (including fluorescence in situ hybridization, spectral karyotyping and comparative genomic hybridization) were applied to study the genotype-phenotype correlation in a Taiwanese family, in which a concomitant segregation of del(13)(q31q31) interstitial deletion and t(13;18)(q32;p11.2) reciprocal translocation in a 2-year-old girl (the proband) was noticed. Two family members (the father and grandmother of the proband) who carried the del(13)(q31q31) but not the translocation t(13;18) both revealed a normal phenotype at adulthood. The finding, which appears novel, that interstitial deletion 13q31 could be associated with a normal phenotype, is therefore valuable in genetic counseling.