Characterization of an Italian founder mutation in the RING-finger domain of BRCA1

The identification of founder mutations in cancer predisposing genes is important to improve risk assessment in geographically defined populations, since it may provide specific targets resulting in cost-effective genetic testing. Here, we report the characterization of the BRCA1 c.190T>C (p.Cys64Arg) mutation, mapped to the RING-finger domain coding region, that we detected in 43 hereditary breast/ovarian cancer (HBOC) families, for the large part originating from the province of Bergamo (Northern Italy). Haplotype analysis was performed in 21 families, and led to the identification of a shared haplotype extending over three BRCA1-associated marker loci (0.4 cM). Using the DMLE+2.2 software program and regional population demographic data, we were able to estimate the age of the mutation to vary between 3,100 and 3,350 years old. Functional characterization of the mutation was carried out at both transcript and protein level. Reverse transcriptase-PCR analysis on lymphoblastoid cells revealed expression of full length mRNA from the mutant allele. A green fluorescent protein (GFP)-fragment reassembly assay showed that the p.Cys64Arg substitution prevents the binding of the BRCA1 protein to the interacting protein BARD1, in a similar way as proven deleterious mutations in the RING-domain. Overall, 55 of 83 (66%) female mutation carriers had a diagnosis of breast and/or ovarian cancer. Our observations indicate that the BRCA1 c.190T>C is a pathogenic founder mutation present in the Italian population. Further analyses will evaluate whether screening for this mutation can be suggested as an effective strategy for the rapid identification of at-risk individuals in the Bergamo area

Interleukin-10 promoter polymorphisms influence susceptibility to ulcerative colitis in a gender-specific manner

Objective. Pathological evidence supports a potential role of the pro- and anti-inflammatory cytokine network in the pathogenesis of inflammatory bowel disease (IBD). Moreover, associated studies suggest a possible involvement of cytokine-related genes in IBD susceptibility. In this study, we evaluated the effect of the anti-inflammatory interleukin-10 (IL10) gene on ulcerative colitis (UC). Material and methods. Two functional single nucleotide polymorphisms (-1082 G/A, -819 T/C) in the IL10 promoter in 203 Italian sporadic UC patients and 391 controls were determined using high-resolution melting analysis. Results. The frequency of the -1082A allele was significantly higher in the UC patients than in controls (p=0.00003); -1082 genotype frequencies were also significantly different between UC patients and controls (p=0.0001). Allele and genotype frequencies of -819 T/C were not significantly associated with UC. Furthermore, the frequencies of haplotypes -1082A/-819C and -1082A/-819T, which have been reported to have a lower promoter activity, were significantly higher in UC patients than in controls (p=0.0004). After gender stratification, we found a significant difference in the -1082A allele (p=0.00004) and genotype (p=0.0002) frequencies only between female UC patients and controls; the same result was obtained for the -1082A/-819C and -1082A/-819T haplotypes (p=0.0006). Conclusions. A gender effect is observed, with women of AG/AA IL10 genotypes and AC/AT haplotypes having a higher risk of developing UC at a younger age. This finding could be related to the previously documented lower IL10 production associated with the -1082A allele and to the IL10 down-regulating effect of estrogens

Sporadic or familial head neck paragangliomas enrolled in a single center: Clinical presentation and genotype/phenotype correlations

BACKGROUND: The purpose of this study was to investigate clinical features and prevalence of germline mutations of patients with head/neck paragangliomas. METHODS: Genetic analysis on known susceptibility genes for paragangliomas (VHL, RET, SDHB, SDHC, SDHD, and SDHAF2) was performed in 17 consecutive patients with head/neck paraganglioma (age range, 14-82 years) and 17 relatives. RESULTS: Head/neck paragangliomas were usually symptomatic with "mass effect" (88.2%), without family history (82.3%), often multifocal (41.2%), never functioning, and malignant. Germline mutations were detected in 7 of 17 patients (41%; 6 SDHD and 1 SDHB). Patients with mutations were younger, with head/neck paragangliomas usually multifocal and with higher biologic aggressiveness than wild-type subjects. To date, 4 families have been studied and the prevalence of carriers was elevated (58.8%). These mutated relatives (age range, 17-71 years) were disease-free, except 4 patients in whom multiple head/neck paragangliomas were detected. CONCLUSION: Adequate morpho-functional screening and follow-up and, if possible, genetic testing is advisable in patients with head/neck paraganglioma. © 2012 Wiley Periodicals, Inc. Head Neck, 2012

A PALB2 germline mutation associated with hereditary breast cancer in Italy

Recently, it has been demonstrated that monoallelic PALB2 mutations predispose to familial breast cancer. We investigated the contribution of PALB2 mutations in a set of 132 Italian BRCA1/BRCA2-negative breast cancer families; one truncating PALB2 mutation, c.2257C>T, resulting in p.Arg753X, was identified in a woman and her daughter, with breast cancer diagnosed at 60 and 31 years old, respectively. This study supports the recent observation that PALB2 mutation are present, although infrequently, in familial BRCA1/BRCA2-negative breast cancer cases; moreover, it sustains latest evidences that some PALB2 mutations are associated with a substantially increased risk of breast cancer

Germline investigation in male breast cancer of DNA repair genes by next-generation sequencing

In order to better define the breast cancer (BC) genetic risk factors in men, a germline investigation was carried out on 81 Male BC cases by screening the 24 genes involved in BC predisposition, genome stability maintenance and DNA repair mechanisms by next-generation sequencing

Founder mutations account for the majority of BRCA1-attributable hereditary breast/ovarian cancer cases in a population from Tuscany, Central Italy

BACKGROUND: Germline mutations in the BRCA1 and BRCA2 tumour-suppressor genes predispose to early-onset breast and ovarian cancer. Although both genes display a highly heterogeneous mutation spectrum, a number of alterations recur in some populations. Only a limited number of founder mutations have been identified in the Italian population so far. OBJECTIVE: To investigate the spectrum of BRCA1/BRCA2 mutations in a set of families originary from the Central-Eastern part of Tuscany and to ascertain the presence of founder effects. We also wanted to approximate the age of the most frequent BRCA1 founder mutation. RESULTS: Overall, four distinct BRCA1 mutations accounted for a large fraction (72.7%) of BRCA1-attributable hereditary breast/ovarian cancer in families originary from this area. We identified common haplotypes for two newly recognised recurrent BRCA1 mutations, c.3228_3229delAG and c.3285delA. The c.3228_3229delAG mutation was estimated to have originated about 129 generations ago. Interestingly, male breast cancer cases were present in 3 out of 11 families with the c.3228_3229delAG mutation. CONCLUSIONS: The observation that a high proportion of families with BRCA1 alterations from Central-Eastern Tuscany harbours a limited number of founder mutations can have significant impact on clinical management of at risk subjects from this area. In addition, the identification of a large set of families carrying an identical mutation that predisposes to breast and ovarian cancer provides unique opportunities to study the effect of other genetic and environmental factors on penetrance and disease phenotype

Germline mutations in MEN1 and BRCA1 genes in a woman with familial multiple endocrine neoplasia type 1 and inherited breast-ovarian cancer syndromes: a case report

The simultaneous occurrence of mutations in two different tumor suppressor genes in the same individual is a very rare event. Here we report the case of a woman in whom germline mutations in both MEN1 and BRCA1 were identified. The severity of MEN1-related biochemical and clinical findings did not significantly differ from that for other affected family members lacking the BRCA1 mutation, except for the development of an extremely large visceral lipoma; the proband has not developed any BRCA1-related malignancies. We explore genetic and molecular rationales for an association between these neoplastic processes

Detection of germline variants in 450 breast/ovarian cancer families with a multi‐gene panel including coding and regulatory regions

With the progress of sequencing technologies, an ever‐increasing number of variants of unknown functional and clinical significance (VUS) have been identified in both coding and noncoding regions of the main Breast Cancer (BC) predisposition genes. The aim of this study is to identify a mutational profile of coding and intron‐exon junction regions of 12 moderate penetrance genes (ATM, BRIP1, CDH1, CHEK2, NBN, PALB2, PTEN, RAD50, RAD51C, RAD51D, STK11, TP53) in a cohort of 450 Italian patients with Hereditary Breast/Ovarian Cancer Syndrome, wild type for germline mutation in BRCA1/2 genes. The analysis was extended to 5′UTR and 3′UTR of all the genes listed above and to the BRCA1 and BRCA2 known regulatory regions in a subset of 120 patients. The screening was performed through NGS target resequencing on the Illumina platform MiSeq. 8.7% of the patients analyzed is carriers of class 5/4 coding variants in the ATM (3.6%), BRIP1 (1.6%), CHEK2 (1.8%), PALB2 (0.7%), RAD51C (0.4%), RAD51D (0.4%), and TP53 (0.2%) genes, while variants of uncertain pathological significance (VUSs)/class 3 were identified in 9.1% of the samples. In intron‐exon junctions and in regulatory regions, variants were detected respectively in 5.1% and in 32.5% of the cases analyzed. The average age of disease onset of 44.4 in non‐coding variant carriers is absolutely similar to the average age of disease onset in coding variant carriers for each pro-band’s group with the same cancer type. Furthermore, there is not a statistically significant difference in the proportion of cases with a tumor onset under age of 40 between the two groups, but the presence of multiple non‐coding variants in the same patient may affect the aggressiveness of the tumor and it is worth underlining that 25% of patients with an aggressive tumor are carriers of a PTEN 3′UTR‐variant. This data provides initial information on how important it might be to extend mutational screening to the regulatory regions in clinical practice