Gain-of-function STAT1 mutation and visceral leishmaniasis

ABSTRACT Gain-of-function mutations in the STAT1 gene have been initially associated with chronic mucocutaneous candidiasis. However, further research has shown that STAT1 GOF variants may increase susceptibility to infection by other intracellular pathogens. This report describes the first case of disseminated leishmaniasis associated with a STAT1 GOF mutation in a pediatric patient who did not have chronic mucocutaneous candidiasis. The patient was a four-year-old boy presenting with fever, severe asthenia, hepatosplenomegaly, pancytopenia, and liver failure. Bone marrow aspirate revealed hemophagocytosis and Leishmania parasites. Treatment consisted primarily of liposomal amphotericin B, as per the Hemophagocytic Lymphohistiocytosis 2004 protocol. After eight weeks of treatment, the patient did not improve and was submitted to diagnostic splenectomy. Activated macrophages and nodular spleen necrosis secondary to the visceral leishmaniasis were detected. Unfortunately, the patient died in the second week after splenectomy due to overwhelming systemic infection. DNA sequencing revealed a pathogenic (p. R274Q) GOF mutation in STAT1.

Risk analysis of recurrence of women with DMD birth history in families with new mutations in DMD gene / 中华检验医学杂志

Objective:To summarize and analyze the risk of pregnancy recurrence of women with Duchenne muscular dystrophy (DMD) birth history in families with new DMD gene mutations, clarify the laws of DMD gene mutations and discuss the mode of genetic counseling in such families.Methods:Collected DMD families from January 2013 to December 2017 in Henan Provincial People′s Hospital. Firstly, the 79 exons of DMD gene were analyzed by multiplex ligation-dependent probe amplification (MLPA) in DMD patients and their mothers. The families that DMD patients with DMD gene mutations but no mutations in their mothers were selected for this study, and then MLPA combined with STR-gene linkage analysis were used to perform prenatal diagnosis for females in these DMD gene new mutation families.Results:A total of 64 families with new DMD gene mutations were included in this study. All mutations were DMD gene exon deletion mutations. A total of 65 fetuses were conducted prenatal diagnosis, included 26 SRY negative, 39 SRY positive; 63 fetuses′ DMD gene normal and 2 fetues′ DMD gene with exon deletion mutations. The results of postpartum follow-up and prenatal diagnosis were consistent.Conclusions:Exon mutations in newly mutated DMD families were mainly manifested as exon deletion, mainly presented in the 45-55 exon region. For families with new DMD mutations, even if there is no DMD gene mutation in women which had reproductive history of DMD, prenatal diagnosis for DMD during pregnancy was still recommended.

First identified Korean family with Tatton-Brown-Rahman Syndrome caused by the novel DNMT3A variant c.118G>C p.(Glu40Gln)

Tatton-Brown-Rahman Syndrome (TBRS), an overgrowth syndrome caused by heterozygous mutation of DNMT3A, first was described in 2014. Approximately 60 DNMT3A variants, including 32 missense variants, have been reported, with most missense mutations located on the DNMT3A functional domains. Autosomal dominant inheritance by germ-line mutation of DNMT3A has been reported, but vertical transmission within a family is extremely rare. Herein, we report the first Korean family with maternally inherited TBRS due to the novel heterozygous DNMT3A variant c.118G>C p.(Glu40Gln), located outside the main functional domain and identified by multigene panel sequencing. The patient and her mother had typical clinical features, including tall stature during childhood, macrocephaly, intellectual disability, and characteristic facial appearance. TBRS shows milder dysmorphic features than other overgrowth syndromes, potentially leading to underdiagnosis and underestimated prevalence; thus, targeted multigene panel sequencing including DNMT3A will be a useful tool in cases of overgrowth and unexplained mild intellectual disability for early diagnosis and genetic counseling.

Smith-Kingsmore syndrome: The first report of a Korean patient with the MTOR germline mutation c.5395G>A p.(Glu1799Lys)

Smith-Kingsmore syndrome (SKS; OMIM 616638), also known as macrocephaly-intellectual disability-neurodevelopmental disorder-small thorax syndrome (MINDS; ORPHA 457485), is a rare autosomal dominant disorder, the prevalence of which is not known. It is caused by a heterozygous germline mutation in MTOR (OMIM 601231). Ten different MTOR germline mutations in 27 individuals have been reported in the medical literature to date. These were all gain-of-function missense variants, and about half of the 27 individuals had c.5395G>A p.(Glu1799Lys) in MTOR. Here, I report for the first time a Korean patient with the heterozygous germline mutation c.5395G>A p.(Glu1799Lys) in MTOR. It was found to be a de novo mutation, which was identified by whole-exome sequencing and confirmed by Sanger sequencing. The patient showed typical clinical features of SKS, including macrocephaly/megalencephaly; moderate intellectual disability; seizures; behavioral problems; and facial dysmorphic features of curly hair, frontal bossing, midface hypoplasia, and hypertelorism.

Clinical and Genetic Characteristics of BRCA1/2 Mutation in Korean Ovarian Cancer Patients: A Multicenter Study and Literature Review / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We investigated the clinical relevance and spectrum of BRCA1/2 mutations in Korean ovarian cancer (KoOC) patients. MATERIALS AND METHODS: Two hundred seventy-nine KoOC patients were enrolled from three university hospitals between 2012 and 2017. Their peripheral blood samples were obtained for BRCA1/2 mutation analysis by direct sequencing. Clinicopathological characteristics were retrospectively reviewed, and spectrum analyses of BRCA1/2 mutation were assessed by systematic literature review. RESULTS: Frequency of BRCA1/2 mutations was 16.5% in KoOC patients. BRCA1/2 mutations were significantly associated with family history of breast/ovarian cancer (pT of BRCA2 in KoBC). CONCLUSION: The clinical relevance of BRCA1/2 mutations in KoOC patients was confirmed but that of early age-of-onset was not. Possible inconsistency in the ratio of BRCA1-to-BRCA2 mutations and the most common mutation between KoOC and KoBC may probably suggest presence of mutation sequence-associated penetrance tendency in hereditary Korean breast and ovarian cancer. These data may provide insights for optimal genetic counseling and prophylactic treatment for at-risk relatives of KoOC patients.

Prevalence of PALB2 Germline Mutations in Early-onset and Familial Breast/Ovarian Cancer Patients from Pakistan / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Partner and localizer of BRCA2 (PALB2) is a breast cancer susceptibility gene that plays an important role in DNA repair. This is the first study assessing the prevalence of PALB2 mutations in early-onset and familial breast/ovarian cancer patients from Pakistan. MATERIALS AND METHODS: PALB2 mutation screening was performed in 370 Pakistani patients with early-onset and familial breast/ovarian cancer, who were negative for BRCA1, BRCA2, TP53, CHEK2, and RAD51C mutations, using denaturing high-performance liquid chromatography analysis. Mutations were confirmed by DNA sequencing. Novel PALB2 alterations were analyzed for their potential effect on protein function or splicing using various in silico prediction tools. Three-hundred and seventy-two healthy controls were screened for the presence of the identified (potentially) functional mutations. RESULTS: A novel nonsense mutation, p.Y743*, was identified in one familial breast cancer patient (1/127, 0.8%). Besides, four in silico-predicted potentially functional mutations including three missense mutations and one 5' untranslated region mutation were identified: p.D498Y, novel p.G644R, novel p.E744K, and novel c.-134_-133delTCinsGGGT. The mutations p.Y743* and p.D498Y were identified in two familial patients diagnosed with unilateral or synchronous bilateral breast cancer at the ages of 29 and 39, respectively. The other mutations were identified in an early-onset (≤ 30 years of age) breast cancer patient each. All five mutations were absent in 372 healthy controls suggesting that they are disease associated. CONCLUSION: Our findings show that PALB2 mutations account for a small proportion of early-onset and hereditary breast/ovarian cancer cases in Pakistan.

Nonautoimmune congenital hyperthyroidism due to p.Asp633Glu mutation in the TSHR gene

Most cases of congenital hyperthyroidism are autoimmune forms caused by maternal thyroid stimulating antibodies. Nonautoimmune forms of congenital hyperthyroidism caused by activating mutations of the thyrotropin receptor (TSHR) gene are rare. A woman gave birth to a boy during an emergency cesarean section at 33 weeks of gestation due to fetal tachycardia. On the 24th day of life, thyroid function tests were performed due to persistent tachycardia, and hyperthyroidism was confirmed. Auto-antibodies to TSHR, thyroid peroxidase, and thyroglobulin were not found. The patient was treated with propylthiouracil and propranolol, but hyperthyroidism was not well controlled. At 3 months of age, the patient had craniosynostosis and hydrocephalus, and underwent a ventriculoperitoneal shunt operation. Direct sequencing of the TSHR gene showed a heterozygous mutation of c.1899C>A (p.Asp633Glu) in exon 10. No mutations were discovered in any of the parents in a familial genetic study. We have reported a case of sporadic nonautoimmune congenital hyperthyroidism, by a missense mutation of the TSHR gene, for the first time in South Korea.

Detection of Germline Mutations in Patients with Epithelial Ovarian Cancer Using Multi-gene Panels: Beyond BRCA1/2 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Next-generation sequencing (NGS) allows simultaneous sequencing of multiple cancer susceptibility genes and may represent a more efficient and less expensive approach than sequential testing. We assessed the frequency of germline mutations in individuals with epithelial ovarian cancer (EOC), using multi-gene panels and NGS. MATERIALS AND METHODS: Patients with EOC (n=117) with/without a family history of breast or ovarian cancer were recruited consecutively, from March 2016 toDecember 2016.GermlineDNAwas sequenced using 35-gene NGS panel, in order to identify mutations. Upon the detection of a genetic alteration using the panel, results were cross-validated using direct sequencing. RESULTS: Thirty-eight patients (32.5%) had 39 pathogenic or likely pathogenic mutations in eight genes, including BRCA1 (n=21), BRCA2 (n=10), BRIP1 (n=1), CHEK2 (n=2), MSH2 (n=1), POLE (n=1), RAD51C (n=2), and RAD51D (n=2). Among 64 patients with a family history of cancer, 27 (42.2%) had 27 pathogenic or likely pathogenic mutations, and six (9.3%) had mutations in genes other than BRCA1/2, such as CHECK2, MSH2, POLE, and RAD51C. Fifty-five patients (47.0%) were identified to carry only variants of uncertain significance. CONCLUSION: Using the multi-gene panel test, we found that, of all patients included in our study, 32.5% had germline cancer-predisposing mutations. NGS was confirmed to substantially improve the detection rates of a wide spectrum of mutations in EOC patients compared with those obtained with the BRCA1/2 testing alone.

p53 gene mutations of familial breast cancer and early-onset breast cancer in part population of southern China / 中南大学学报(医学版)

Objective:To investigate the site and characteristic ofp53 gene mutations in familial or early-onset breast cancer patients in part population of southern China.Methods:A total of 150 patients with familial and early-onset breast cancer in parts population of southern China were enrolled.Genomic DNA was isolated from each peripheral blood sample,and the entire coding sequence and exon and intron splicing region of p53 gene were amplificated by PCR in the 150 patients.The mutation analysis were detected by denaturing high performance liquid chromatography (DHPLC) and confirmed by DNA sequence analysis.Results:In the 150 patients with familial and early-onset breast cancer,6 mutations including one novel pathogenic mutation 869_888 ins20 (insert mutation) and 5 previously reported pathogenic mutations (deletion mutation 643_660de118 and 4 missense mutation 91G＞A,215C＞G,537T＞G,743G＞A) were identified in p53 gene encoding region in 9 patients of breast cancer.Moreover,one same sense mutation 141G＞A in exon 4,one 16 bases deletion in intron 3,and 9 single nucleotide polymorphisms in p53 gene introns were also identified.The total mutation frequency ofp53 gene in 150 patients with familial breast cancer and early-onset breast cancer from part population of southern China was 6.00％,and the mutation frequency of familial breast cancer and early-onset breast cancer was 6.81％ and 6.25％,respectively.Conclusion:The total mutation frequency ofp53 gene in 150 patients with familial breast cancer and early-onset breast cancer from partpopulation of southern China is higher than the frequency previously reported.The pathogenicity of the novel mutations (insert mutation) 869_888ins20 will be confirmed by function analysis in the future study.The deletion mutation 643_660de118 enriches the p53 gene mutation database among Chinese population,which is probably the specific mutation of breast cancer in Chinese population.

Case Report of Menopausal Woman Diagnosed with Endometrial Cancer after Colon Cancer with Germline Mutation in MSH6 in Korea

We present a case of an endometrial cancer patient with germline mutation in MutS homolog 6 (MSH6), associated with Lynch syndrome. A 60-year-old Korean woman had a personal history of colon cancer 23 years ago. She also had a family history of endometrial cancer and colon cancer of her sisters and brothers. Immunohistochemistry was negative for MutL homolog 1 (MLH1) and positive for MutS homolog 2 (MSH2). Based on these findings, she underwent genetic counseling and testing that revealed a frameshift germline mutation at MSH6 (c. 3261dupC).

Neuroendocrine Tumors in the Stomach, Duodenum, and Pancreas Accompanied by Novel MEN1 Gene Mutation / 대한소화기학회지

Multiple endocrine neoplasia type 1 (MEN1) syndrome is a relatively rare disease, characterized by the occurrence of multiple endocrine tumors in the parathyroid and pituitary glands as well as the pancreas. Here, we report a case of MEN1 with neuroendocrine tumors (NETs) in the stomach, duodenum, and pancreas. A 53-year-old man visited our hospital to manage gastric NET. Five years prior to his visit, he had undergone surgery for incidental meningioma. His brother had pancreatic nodules and a history of surgery for adrenal adenoma. His brother's daughter also had pancreatic nodules, but had not undergone surgery. The lesion was treated by endoscopic submucosal dissection and diagnosed as a grade 1 NET. Another small NET was detected in the second duodenal portion, resected by endoscopic submucosal dissection, which was also diagnosed as a grade 1 NET. During evaluation, three nodules were detected in the pancreas, and no evidence of pituitary, parathyroid tumors, or metastasis was observed. After surgery, the pancreatic lesions were diagnosed as NETs, with the same immunohistochemical patterns as those of the stomach and duodenum. Genetic testing was performed, and a heterozygous mutation was detected in the MEN1 gene, which is located on 11q13.

A Novel Germline Mutation in BRCA1 Causes Exon 20 Skipping in a Korean Family with a History of Breast Cancer / 한국유방암학회지

Germline mutations in the BRCA1 and BRCA2 genes are strong genetic factors for predispositions to breast, ovarian, and other related cancers. This report describes a family with a history of breast and ovarian cancers that harbored a novel BRCA1 germline mutation. A single nucleotide deletion in intron 20, namely c.5332+4delA, was detected in a 43-year-old patient with breast cancer. This mutation led to the skipping of exon 20, which in turn resulted in the production of a truncated BRCA1 protein that was 1773 amino acids in length. The mother of the proband had died due to ovarian cancer and had harbored the same germline mutation. Ectopically expressed mutant BRCA1 protein interacted with the BARD1 protein, but showed a reduced transcriptional function, as demonstrated by the expression of cyclin B1. This novel germline mutation in the BRCA1 gene caused familial breast and ovarian cancers.

A rare pseudomyxoma peritonei with a MSH2 variation of unknown significance and two mutation carrier family members

Pseudomyxoma peritonei (PMP) is a rare tumor that usually originates in the appendix, but a small number of cases originate in the ovary. Lynch syndrome (LS) is an autosomal dominant hereditary condition that increases the risk of cancer, particularly in the colon and endometrium. Mutations in the mismatch repair genes (MSH2, MLH1, MSH6, and PMS2) increase the risk of LS. Reported PMP cases with hereditary gene mutations of unknown significance are also rare. Here, we investigated a PMP patient and her family members, who have an MSH2 variant of unknown significance. Physicians have an important role in counseling, management, and surveillance based on genetics and pathogenicity.

Estudo da Beta-catenina em tumores adrenocorticais humanos / Study of beta-catenin in human adrenocortical tumors

Introdução: A incidência de tumores adrenocorticais em crianças é particularmente elevada nas regiões sudeste e sul do Brasil, correlacionandose com a ocorrência da mutação germinativa p.R337H do supressor tumoral p53, entretanto, o carcinoma adrenocortical é uma neoplasia endócrina maligna rara em todo o mundo com uma incidência aproximada de 0,5 - 2 casos por milhão por ano. Esta condição é uma doença heterogênea, apresentando frequentemente comportamento clínico agressivo e letal. A cascata de sinalização Wnt é uma via importante de transdução de sinal em cânceres humanos e tem sido implicada na tumorigênese adrenocortical. A atividade desta via de sinalização é dependente da quantidade de beta-catenina citoplasmática e nuclear. Mutações ativadoras no gene da beta-catenina (CTNNB1) foram relatadas em diversas neoplasias humanas. Estudos demonstraram que mutações no gene CTNNB1 são os defeitos genéticos mais frequentemente encontrados em adenomas e em carcinomas adrenocorticais. O estudo destas mutações demonstrou que as alterações no gene CTNNB1 localizam-se principalmente exon 3, que codifica a porção amino terminal da beta- catenina. Objetivos: determinar a ocorrência e a frequência das mutações somáticas no exon 3 do gene CTNNB1. Adicionalmente, determinar a imunorreatividade de beta-catenina e de p53 em tumores adrenocorticais benignos e malignos de crianças e adultos. Correlacionar os resultados da análise de mutações gênicas e os dados de imunorreatividade com as características hormonais, a mutação p.R337H do p53, o diagnóstico histológico e a evolução dos tumores adrenocorticais de crianças e adultos. Métodos: Neste estudo, a análise de imunohistoquímica para beta-catenina e p53 foi realizada em 103 tumores adrenocorticais benignos e malignos (40 crianças e 63 adultos), estando as amostras histológicas alocadas em micromatriz tecidual (TMA). A pesquisa de mutações no exon 3 do gene CTNNB1 foi determinada por seqüenciamento automático em 64 tumores...

Introduction: The incidence of adrenocortical tumors in children is particularly high in the southeastern and southern regions of Brazil, correlating with the occurrence of p.R337H p53 tumor suppressor germline mutation. However, adrenocortical carcinoma is a worldwide rare endocrine malignancy with an approximate incidence of 0.5 to 2 cases per million per year. This condition is a heterogeneous disease and is often lethal. The Wnt signaling pathway is an important signal transduction pathway in human cancers and has been implicated in adrenocortical tumorigenesis. The activity of this signaling pathway is dependent on the amount of nuclear and cytoplasmic beta-catenin. Activating mutations of ?-catenin (CTNNB1) gene have been reported in several human malignancies. Studies have shown that CTNNB1 mutations are the most common genetic defect found in adrenocortical adenomas and carcinomas. The study of these mutations demonstrated that the changes in CTNNB1 gene are mainly located in exon 3, which encodes the amino terminal portion of the beta- catenin. Objectives: to determine the occurrence and frequency of CTNNB1 somatic mutations and the abnormal beta-catenin and p53 accumulation in benign and malignant adrenocortical tumors in both children and adults. We also evaluated the correlation of the gene mutations analysis and immunohistochemistry data with the hormonal characteristics, the p.R337H germline mutation, the histological diagnosis and the prognosis of adrenocortical tumors in children and adults. Methods: In this study, immunohistochemistry for beta-catenin and p53 was performed in 103 benign and malignant (40 children and 63 adults) adrenocortical tumors. The histological samples were allocated in a tissue microarray (TMA). The study of the CTNNB1 gene was performed by direct sequencing of 64 adrenocortical tumors. Results: The beta-catenin abnormal accumulation was similar in benign and malignant adrenocortical tumors of children and adults (15...(au)

Genetic and Epigenetic Analysis in Korean Patients with Multiple Endocrine Neoplasia Type 1

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a familial syndrome characterized by the parathyroid, pancreas and pituitary tumors. Parathyroid tumors are the most common clinical manifestations, occurring in more than 90% of MEN1 patients. Heterozygous germline mutations of the MENIN gene underlie the tumorigenesis in MEN1 and epigenetic alterations along with germline mutations may contribute to tumorigenesis. Here, we investigated the associations between genotype and phenotype in Korean MEN1 patients. METHODS: We analyzed medical records from 14 unrelated MEN1 patients who had newly confirmed MENIN germline mutations, together with 14 previous reports in Korea. Aberrant DNA methylations were also examined in MEN1-related parathyroid tumors using the Infinium HumanMethylation 450 BeadChip. RESULTS: Total 28 germline mutations of MENIN were relatively highly concentrated in exons 7 and 8 compared to previous reports from Western countries. Six mutations (c.111dupT/p.S38Ffs*79, c.225_226insT/p.T76Yfs*41, c.383_398del16/p.S128Tfs*52, c.746dupT/p.H250Afs*20, c.1150G>T/p.E384*, and c.1508G>A/p.G503N) were newly found in the present study. Of interest, four patients (15%) showed unusual initial presentations and three patients were diagnosed incidentally at the general medical checkup. We also found three distinct sites in exon 2 of MENIN were significantly hypomethylated in the MEN1 parathyroid tumors, comparing correspondent blood samples. CONCLUSION: We also have found a lack of genotype/phenotype correlation in Korean MEN1 patients. There were not a few unusual initial manifestations in MEN1 patients, thus, genetic testing for the MENIN germline mutations can provide important information for the better prognosis. Further studies are warranted to investigate altered DNA methylations in the MENIN gene involved in tumorigenesis.

Characteristics of the Germline MEN1 Mutations in Korea: A Literature Review / 대한내분비외과학회지

PURPOSE: Multiple endocrine neoplasia type 1 (MEN-1) is an autosomal dominant disease caused by the MEN1 germline mutation. We reviewed previous reports in order to summarize the characteristics of germline MEN1 mutation in Korea. METHODS: We retrieved the relevant literature regarding MEN1 germline mutation in Korea using the Pubmed (http://www.pubmed.org/) and Koreamed (http://www.koreamed.org/) databases from 2000 to 2012. We evaluated the pedigree of the patients in order to exclude the same, repeated families. We collected all data on the types of mutations and clinical characteristics. RESULTS: There were nine studies with 12 cases of MEN1 mutations in Korea. Two cases were sporadic MEN-1. C.196_200dupAGCCC was reported in three families. There were six cases of frameshift mutation, three cases of missense mutation, two cases of nonsense mutation, and one case of splice site mutation. Five mutations were novel mutations not previously reported. CONCLUSION: We summarized the characteristics of germline MEN1 mutations in Korea. Genetic testing of MEN1 is rare in Korea; however, it will be useful in preclinical diagnosis and genetic counseling.

Bilateral adrenal pheochromocytoma with a germline L790F mutation in the RET oncogene / 대한외과학회지

About ten percent of pheochromocytomas are associated with familial syndrome. Hereditary pheochromocytoma has characteristics of early onset, multifocality and bilaterality. We experienced a case of 44-year-old man with bilateral pheochromocytoma without evidence of medullary thyroid cancer. Genetic test detected a L790F germline mutation of RET oncogene. The author found a necessity for genetic tests in cases of young-age, bilateral pheochromocytoma.

Análise clínica e molecular de pacientes com distúrbios do desenvolvimento gonadal / Clinical and molecular analysis of patients with disorders of gonadal development

Introdução: O termo distúrbios do desenvolvimento gonadal (DDG) inclui condições congênitas nas quais o desenvolvimento gonadal é atípico. Estudos feitos em camundongos observaram que alguns genes como o Cbx2 e o Tcf21 interferem na fase inicial do desenvolvimento gonadal, afetando tanto gônadas XX quanto XY. O gene Dhh, por sua vez, codifica o fator de transcrição Dhh, produzido pelas células de Sertoli, que é fundamental para a diferenciação das células de Leydig em gônadas XY. Nos ovários, o gene FOXL2 atua na foliculogênese, sendo fundamental para a formação dos ovários. Objetivos: Analisar clinicamente e pesquisar anormalidades nos genes CBX2, TCF21, DHH e FOXL2 em pacientes portadores de distúrbios do desenvolvimento gonadal 46, XY e 46, XX. Material e Métodos: Foram estudados 60 pacientes (41 com DDG 46, XY e 19 com DDG 46, XX). A análise molecular foi realizada a partir da amplificação gênica por PCR e sequenciamento direto. Resultados: Várias alterações alélicas foram encontradas nos quatro genes, algumas ainda não descritas na literatura. Uma alteração intrônica no gene DHH foi encontrada em um paciente com DDG 46, XY e não foi encontrada em nenhum dos 360 alelos normais estudados (g.IVS2 +29G>A). Estudamos essa variante através da extração do RNA do testículo do paciente afetado, mas não encontramos alteração no RNA; portanto ela parece não ser uma mutação. No gene TCF21, a variante encontrada foi identificada em controles normais. No gene CBX2, das treze alterações encontradas, uma não foi identificada em 206 alelos normais, e há troca de aminoácidos (p.C132R / g.394 T>C). Trata-se de uma variante que pode ter relação com o fenótipo do paciente, portador de DDG 46, XY. No gene FOXL2, das três alterações encontradas, uma não foi identificada em 206 alelos normais; contudo, não há troca de aminoácidos (p.A181A / g.543 C>T). Conclusão: Esse estudo sugere que mutações nos genes CBX2, TCF21, FOXL2 e DHH são causas raras de distúrbios do desenvolvimento...

Introduction: Congenital disorders of gonadal development (DGD) include conditions whose gonadal development is atypical. Studies in mice found that some genes such as Cbx2 and Tcf21 interfere in the initial phase of gonadal development, affecting both XX and XY gonads. Dhh gene, in turn, encodes the transcription factor Dhh, produced by Sertoli cells, which is essential for the differentiation of Leydig cells in XY gonads. In the ovaries, genes as FOXL2 act in folliculogenesis, fundamental to the development of the ovaries. Objectives: To analyze patients with disorders of gonadal development (DGD) 46, XY and 46, XX and research mutations in CBX2, TCF21, DHH and FOXL2 genes. Methods: We analyzed 60 patients (41 DGD 46, XY patients and 19 DGD 46, XX patients). The whole coding region of CBX2, TCF21, DHH and FOXL2 genes were amplified by PCR and direct sequenced. Results: Several allelic variations have been found in the four genes, some not even described by literature. One intronic variation in DHH was described in one patient with 46, XY DGD and it wasnt found in any of the 360 normal control alleles studied (g.IVS2 +29G>A). We studied this variant through RNA extraction from the affected patients testes, but we didnt find any alteration in the RNA, so it doesnt seem to be a mutation. In TCF21 gene, the single variant that was found was identified in normal controls. In CBX2 gene, among the 13 alterations described, one wasnt identified in 206 normal control alleles, and there is aminoacid change (p.C132R / g.394 T>C). This is a variant that may be a mutation, causing the patients phenotype that had 46, XY DGD. In FOXL2, among the 3 variations described, one wasnt indentified in 206 normal control alleles, but there wasnt amino acid change (p.A181A / g.543 C>T).Conclusion: This study suggests that mutations in CBX2, TCF21, FOXL2 and DHH genes are rarely causes of disorders of gonadal development.

Predisposition of genetic disease by modestly decreased expression of GCH1 mutant allele

Recently it was shown that single nucleotide polymorphisms (SNPs) can explain individual variation because of the small changes of the gene expression level and that the 50% decreased expression of an allele might even lead to predisposition to cancer. In this study, we found that a decreased expression of an allele might cause predisposition to genetic disease. Dopa responsive dystonia (DRD) is a dominant disease caused by mutations in GCH1 gene. The sequence analysis of the GCH1 in a patient with typical DRD symptoms revealed two novel missense mutations instead of a single dominant mutation. Family members with either of the mutations did not have any symptoms of DRD. The expression level of a R198W mutant allele decreased to about 50%, suggesting that modestly decreased expression caused by an SNP should lead to predisposition of a genetic disease in susceptible individuals.

The Characteristics of Multiple Endocrine Neoplasia in Korean / 대한내분비외과학회지

PURPOSE: Multiple Endocrine Neoplasm (MEN) is a rare, complex and familial disease. There are MEN syndromes are inherited in an autosomal dominant fashion with high penetrance. The variations in the RET gene play an important role in the MEN syndromes. Recent advances in diagnosis, treatment and genetic study of patients with MEN in Korean are reviewed. METHODS: There were 79 cases and 20 families with MEN syndromes in Korea which based on my experiences and 27 published papers. According to subtypes, there were classified and analyzed. RESULTS: Mean age was 37.9±11.5 years old. Sex ratio was 1:2.6. There were 7 families and 23 cases with MEN type I in Korean. The clinical characteristics of MEN I in Korean are mostly not different from the previous reports except older age (mean=43.2 old-year) at diagnosis. The frequency of the MEN I germ-line mutation in Korean MEN I (80%) families was similar to those reported previously. There were 13 families and 52 cases with MEN type II A in Korean. Three-quarters (9/12) of the Korean patients with MEN IIa had RET mutations on codon 634 of exon 11 (4 patients, C634; 4 patients, C634Y; 1 patient, C634W), but a quarter (3/12) had mutations on codon 618 of exon 10 (2 patients, C618R; 1 patient, C618S). A small medullary carcinoma in a patient of MEN type II A family was detected by genetic mutation screening in SMC. MEN IIb was reported only 4 cases. A case showed a codon 918 mutation (M918T) at exon 16 of RET proto-oncogene. CONCLUSION: Multiple endocrine neoplasia is rare hereditary cancer syndromes expressing a variety of tumors. With understanding of the molecular and clinical pathology of MEN syndromes, genetic screening is now feasible, and treatments have become more individualized based on genetic information of Korean.