Analysis of FANCA gene mutation in a child with refractory leukocytopenia and thrombocytopenia / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis of a child affected with refractory leukocytopenia and thrombocytopenia.@*METHODS@#Clinical manifestation and auxiliary examination of the child were discussed. Whole exome next generation sequencing (NGS) and multiplex ligation-dependent probe amplification (MLPA) were used to detected potential mutations of the FANCA gene.@*RESULTS@#Repeated blood tests indicated that the child had abnormal WBC count at (2.7-3.98)×10

Prevalencia de intento de suicidio adolescente y factores de riesgo asociados en una comuna rural de la provincia de Concepción / Suicide attempts among Chilean adolescents

Background: Suicide mortality rates are increasing among teenagers. Aim: To study the prevalence and predictive factors of suicide attempts among Chilean adolescents. Material and Methods: A random sample of 195 teenagers aged 16 ± 1 years (53% males) answered an anonymous survey about their demographic features, substance abuse, the Osaka suicidal ideation questionnaire, Smilksten familial Apgar. Beck hopelessness scale, Beck depression scale and Coppersmith self-esteem inventory. Results: Twenty five percent of respondents had attempted suicide at least in one occasion during their lives. These attempts were significantly associated with female gender, absent parents, family dysfunction, drug abuse, smoking, low self-esteem, hopelessness, depression and recent suicidal ideation. A logistic regression analysis accepted female gender, smoking and recent suicidal ideation as significant independent predictors of suicide attempt. Conclusions: Suicide attempted is common among teenagers and its predictors are female sex, smoking and previous suicidal ideation.

Molecular and prenatal diagnosis of a family with Fanconi anemia by next generation sequencing / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To provide prenatal diagnosis for a pregnant woman who had given birth to a child with Fanconi anemia with combined next-generation sequencing (NGS) and Sanger sequencing.</p><p><b>METHODS</b>For the affected child, potential mutations of the FANCA gene were analyzed with NGS. Suspected mutation was verified with Sanger sequencing. For prenatal diagnosis, genomic DNA was extracted from cultured fetal amniotic fluid cells and subjected to analysis of the same mutations.</p><p><b>RESULTS</b>A low-frequency frameshifting mutation c.989_995del7 (p.H330LfsX2, inherited from his father) and a truncating mutation c.3971C>T (p.P1324L, inherited from his mother) have been identified in the affected child and considered to be pathogenic. The two mutations were subsequently verified by Sanger sequencing. Upon prenatal diagnosis, the fetus was found to carry two mutations.</p><p><b>CONCLUSION</b>The combined next-generation sequencing and Sanger sequencing can reduce the time for diagnosis and identify subtypes of Fanconi anemia and the mutational sites, which has enabled reliable prenatal diagnosis of this disease.</p>

A Case Report of Fanconi Anemia Diagnosed by Genetic Testing Followed by Prenatal Diagnosis

Fanconi anemia (FA) is a rare genetic disorder affecting multiple body systems. Genetic testing, including prenatal testing, is a prerequisite for the diagnosis of many clinical conditions. However, genetic testing is complicated for FA because there are often many genes that are associated with its development, and large deletions, duplications, or sequence variations are frequently found in some of these genes. This study describes successful genetic testing for molecular diagnosis, and subsequent prenatal diagnosis, of FA in a patient and his family in Korea. We analyzed all exons and flanking regions of the FANCA, FANCC, and FANCG genes for mutation identification and subsequent prenatal diagnosis. Multiplex ligation-dependent probe amplification analysis was performed to detect large deletions or duplications in the FANCA gene. Molecular analysis revealed two mutations in the FANCA gene: a frameshift mutation c.2546delC and a novel splice-site mutation c.3627-1G>A. The FANCA mutations were separately inherited from each parent, c.2546delC was derived from the father, whereas c.3627-1G>A originated from the mother. The amniotic fluid cells were c.3627-1G>A heterozygotes, suggesting that the fetus was unaffected. This is the first report of genetic testing that was successfully applied to molecular diagnosis of a patient and subsequent prenatal diagnosis of FA in a family in Korea.

Construction of FANCA mutant protein from Fanconi anemia patient and analysis of its function / 中华血液学杂志

<p><b>OBJECTIVE</b>To study FANCA protein expression in Fanconi anemia patient's (FA) cells and explore its function.</p><p><b>METHODS</b>FANCA protein expression was analyzed in 3 lymphoblast cell lines derived from 3 cases of type A FA (FA-A) patients using Western blot. Nucleus and cytoplasm localization of FANCA protein was analyzed in one case of FA-A which contained a truncated FANCA (exon 5 deletion). The FANCA mutant was constructed from the same patient and its interaction with FANCG was evaluated by mammalian two-hybrid (M2H) assay.</p><p><b>RESULTS</b>FANCA protein was not detected in the 3 FA-A patients by rabbit anti-human MoAb, but a truncated FANCA protein was detected in 1 of them by mouse anti-human MoAb. The truncated FANCA could not transport from cytoplasm into nucleus. The disease-associated FANCA mutant was defective in binding to FANCG in M2H system.</p><p><b>CONCLUSIONS</b>FANCA proteins are defective in the 3 FA-A patients. Disfunction of disease-associated FANCA mutant proved to be the pathogenic mutations in FANCA gene. Exon 5 of FANCA gene was involved in the interaction between FANCA and FANCG.</p>

Overexpression of the Fanconi Anemia A Gene in Hela and MCF10A Cells

BACKGROUND: Fanconi Anemia (FA) is an autosomal recessive inherited disease, which is characterized by developmental abnormalities, progressive bone marrow failure and a predisposition to cancer. The phenotypes of FA cells show extreme sensitivities towards oxygen and DNA cross linking agents, such as diepoxybutane and mitomycin C (MMC). METHODS: In the current study, retroviruses expressing the FANCA gene were prepared to create the stable cell lines, Hela (cervical carcinoma) and MCF10A (breast). The expression of FANCA protein in the Hela and MCF10A stable cells, following puromycin selection, was checked using Western blot. The difference in the cell growth between the parent and FANCA expressing cells following MMC treatment was checked using the MTT assay. RESULTS: The expression of exogenous FANCA protein in the Hela and MCF10A stable cells was observed using Western blot. The MCF10A cells expressing exogenous FANCA were resistant to MMC concentrations with the range 0.01~1 micrometer compared with the MCF10 parent cells. However, at an MMC concentration of 10 micrometer, there was no difference in the susceptibility between the parent and FANCA expressing MCF10 cells. The Hela cells expressing FANCA showed no resistance at any MMC concentration (0.01~10 micrometer). CONCLUSION: FANCA protein is an important factor for resistance to the cross linking agent, MMC, in MCF10A breast cells, but not in Hela cervical carcinoma cells.

FANCA gene mutation analysis in Fanconi anemia patients / 中华血液学杂志

<p><b>OBJECTIVE</b>To screen the FANCA gene mutation and explore the FANCA protein function in Fanconi anemia (FA) patients.</p><p><b>METHODS</b>FANCA protein expression and its interaction with FANCF were analyzed using Western blot and immunoprecipitation in 3 cases of FA-A. Genomic DNA was used for MLPA analysis followed by sequencing.</p><p><b>RESULTS</b>FANCA protein was undetectable and FANCA and FANCF protein interaction was impaired in these 3 cases of FA-A. Each case of FA-A contained biallelic pathogenic mutations in FANCA gene.</p><p><b>CONCLUSIONS</b>No functional FANCA protein was found in these 3 cases of FA-A, and intragenic deletion, frame shift and splice site mutation were the major pathogenic mutations found in FANCA gene.</p>

Molecular analysis of the most prevalent mutations of the FANCA and FANCC genes in Brazilian patients with Fanconi anaemia

Fanconi anaemia (FA) is a recessive autosomal disease determined by mutations in genes of at least eleven complementation groups, with distinct distributions in different populations. As far as we know, there are no reports regarding the molecular characterisation of the disease in unselected FA patients in Brazil. OBECTIVE: This study aimed to investigate the most prevalent mutations of FANCA and FANCC genes in Brazilian patients with FA. METHODS: Genomic DNA obtained from 22 racially and ethnically diverse unrelated FA patients (mean age ± SD: 14.0 ± 7.8 years; 10 male, 12 female; 14 white, 8 black) was analysed by polymerase chain reaction and restriction site assays for identification of FANCA (delta3788-3790) and FANCC (delta322G, IVS4+4A -> T, W22X, L496R, R548X, Q13X, R185X, and L554P) gene mutations. RESULTS: Mutations in FANCA and FANCC genes were identified in 6 (27.3 percent) and 14 (63.6 percent) out of 22 patients, respectively. The disease could not be attributed to the tested mutations in the two remaining patients enrolled in the study (9.1 percent). The registry of the two most prevalent gene abnormalities (delta3788-3790 and IVS4 + 4 -> T) revealed that they were present in 18.2 percent and 15.9 percent of the FA alleles, respectively. Additional FANCC gene mutations were found in the study, with the following prevalence: delta322G (11.4 percent), W22X (9.1 percent), Q13X (2.3 percent), L554P (2.3 percent), and R548X (2.3 percent) of total FA alleles. CONCLUSION: These results suggest that mutations of FANCA and FANCC genes are the most prevalent mutations among FA patients in Brazil.