Frequency of the CHEK2 1100delC Mutation among Women with Breast Cancer: An International Study (original) (raw)

Absence of CHEK2 1100delC mutation in familial breast cancer cases from a South American population

Breast Cancer Research and Treatment, 2008

Dear EditorThe most widely accepted model proposes that familial breast cancer susceptibility is a consequence of a small number of mutations in BRCA1 or BRCA2 (BRCA1/2) and a much higher proportion of mutations in ethnic-specific genes of moderate and/or low penetrance [1]. CHEK2 gene, involved in DNA damage and replication checkpoints, has been pointed out as a good candidate. Moreover, a specific variant in this gene, 1100delC, has been found to increase breast cancer susceptibility among familial breast cancer cases not attributable to mutations in BRCA1/2 [2]. Most of the studies evaluating this mutation as a female breast cancer susceptibility allele have been conducted in European populations, where the prevalence of the variant in controls ranged from 0 out of 400 controls in Spain to 2.8% in the Netherlands (Table 1). This variant has been detected in a considerable higher proportion (4–11%) in patients with a positive family history of breast cancer (usually known to be BRCA1 ...

Genetic modifiers of CHEK2*1100delC-associated breast cancer risk

Genetics in medicine : official journal of the American College of Medical Genetics, 2016

CHEK2*1100delC is a founder variant in European populations that confers a two- to threefold increased risk of breast cancer (BC). Epidemiologic and family studies have suggested that the risk associated with CHEK2*1100delC is modified by other genetic factors in a multiplicative fashion. We have investigated this empirically using data from the Breast Cancer Association Consortium (BCAC). Using genotype data from 39,139 (624 1100delC carriers) BC patients and 40,063 (224) healthy controls from 32 BCAC studies, we analyzed the combined risk effects of CHEK2*1100delC and 77 common variants in terms of a polygenic risk score (PRS) and pairwise interaction. The PRS conferred odds ratios (OR) of 1.59 (95% CI: 1.21-2.09) per standard deviation for BC for CHEK2*1100delC carriers and 1.58 (1.55-1.62) for noncarriers. No evidence of deviation from the multiplicative model was found. The OR for the highest quintile of the PRS was 2.03 (0.86-4.78) for CHEK2*1100delC carriers, placing them in ...

The CHEK2 1100delC allelic variant is not present in familial and sporadic breast cancer cases from Moroccan population

SpringerPlus, 2015

Purpose: The cell-cycle checkpoint kinase 2 (CHEK2) is an important signal transducer of cellular responses to DNA damage, whose defects has been associated with increased risk for breast cancer. The CHEK2 1100delC mutation has been reported to confer a twofold increased risk of breast cancer among carriers. The frequency of the mutation varies among populations. The highest frequency has been described in Northern and Eastern European countries. However, the 1100delC mutation has been investigated in different case-control studies and none in Moroccan population. The aim of this study was to evaluate the prevalence of this variant and determine its contribution to the development of breast cancer in sporadic cases and also in members of breast cancer families who tested negative or positive for a deleterious mutation in BRCA1/BRCA2. Methods: In this case-control study we performed the CHEK2 1100delC mutation analysis by ASO-PCR in 134 breast cancer patients and 114 unaffected control individuals. Most of these families had several cases of breast cancer or ovarian cancer (or both). Results: No CHEK2 1100delC mutations were detected in any of 134 individuals, including 59 women diagnosed with breast cancer at an early age (<40 years), 10 women with bilateral breast cancer, and 6 women with ovarian cancer. Conclusion: Our preliminary genetic analysis are consistent with the reported very low frequency of CHEK2 1100delC mutation in North American populations (compared with Northern Europe), rendering CHEK2 1100delC such as an unlikely to be major breast cancer susceptibility genes.

CHEK2*1100delC homozygosity in the Netherlands-prevalence and risk of breast and lung cancer

European Journal of Human Genetics, 2014

The 1100delC mutation in the CHEK2 gene has a carrier frequency of up to 1.5% in individuals from North-West Europe. Women heterozygous for 1100delC have an increased breast cancer risk (odds ratio 2.7). To explore the prevalence and clinical consequences of 1100delC homozygosity in the Netherlands, we genotyped a sporadic breast cancer hospital-based cohort, a group of non-BRCA1/2 breast cancer families, and breast tumors from a tumor tissue bank. Three 1100delC homozygous patients were found in the cohort of 1434 sporadic breast cancer patients, suggesting an increased breast cancer risk for 1100delC homozygotes (odds ratio 3.4, 95% confidence interval 0.4-32.6, P ¼ 0.3). Another 1100delC homozygote was found in 592 individuals from 108 non-BRCA1/2 breast cancer families, and two more were found after testing 1706 breast tumors and confirming homozygosity on their wild-type DNA. Follow-up data was available for five homozygous patients, and remarkably, three of them had developed contralateral breast cancer. A possible relationship between 1100delC and lung cancer risk was investigated in 457 unrelated lung cancer patients but could not be confirmed. Due to the small number of 1100delC homozygotes identified, the breast cancer risk estimate associated with this genotype had limited accuracy but is probably higher than the risk in heterozygous females. Screening for CHEK2 1100delC could be beneficial in countries with a relatively high allele frequency.

A risk of breast cancer in women - carriers of constitutional CHEK2 gene mutations, originating from the North - Central Poland

Hereditary Cancer in Clinical Practice, 2014

Background: Germline mutations of the CHEK2 gene have been reported to be associated with breast cancer. In this study, we analyzed the association of CHEK2 mutations with the risk of development of breast cancer in women of North-Central Poland. Methods: 420 women with breast cancer and 435 controls were tested for three protein truncating (IVS2 + 1G > A, 1100delC, del5395) and one missense (I157T) CHEK2 mutation. IVS2 + 1G > A and I157T mutations were identified by RFLP-PCR, 1100delC variant was analyzed using an ASO-PCR and del5395 mutation by multiplex-PCR. The statistical tests: the odds ratio (OR) and Fisher's exact test were used. Results: In 33 out of 420 (7.9%) women consecutively diagnosed with breast cancer, we detected one of four analyzed CHEK2 mutations: I157T, 1100delC, IVS2 + 1G > A or del5395. Together they were not associated with the increased risk of breast cancer (North-Central control group: OR = 1.6, p = 0.124; the general Polish population: OR = 1.4, p = 0.109). This association was only seen for IVS2 + 1G > A mutation (OR = 3.0; p = 0.039). One of the three truncating CHEK2 mutations (IVS2 + 1G > A, 1100delC, del5395) was present in 9 of 420 women diagnosed with breast cancer (2.1%) and in 4 of 121 women (3.3%) with a history of breast cancer in a first-and/or second-degree relatives. Together they were associated with the increased risk of disease in these groups, compared to the general Polish population (OR = 2.1, p = 0.053 and OR = 3.2; p = 0.044, respectively). I157T mutation was detected in 25 of 420 women diagnosed with breast cancer (6.0%) and in 8 of 121 women (6.6%) with a history of breast cancer in first-and/or second-degree relatives. The prevalance of I157T mutation was 4.1% (18/435) in North-Central control group and 4.8% (265/5.496) in the general Polish population. However it was not associated with an increased risk of breast cancer. Conclusion: Obtained results suggest that CHEK2 mutations could potentially contribute to the susceptibility to breast cancer. The germline mutations of CHEK2, especially the truncating ones confer low-penetrance breast cancer predisposition that contribute significantly to familial clustering of breast cancer at the population level.

Frequency of CHEK2*1100delC in New York breast cancer cases and controls

BMC Medical Genetics, 2003

The 1100delC CHEK2 allele has been associated with a 1.4-4.7 fold increased risk for breast cancer in women carrying this mutation. While the frequency of 1100delC was 1.1-1.4% in healthy Finnish controls, the frequency of this allele in a North American control population and in North American breast cancer kindreds remains unclear.

Risk of Breast Cancer in Women With a CHEK2 Mutation With and Without a Family History of Breast Cancer

Journal of Clinical Oncology, 2011

Purpose To estimate the risk of breast cancer in a woman who has a CHEK2 mutation depending on her family history of breast cancer. Patients and Methods Seven thousand four hundred ninety-four BRCA1 mutation–negative patients with breast cancer and 4,346 control women were genotyped for four founder mutations in CHEK2 (del5395, IVS2+1G>A, 1100delC, and I157T). Results A truncating mutation (IVS2+1G>A, 1100delC, or del5395) was present in 227 patients (3.0%) and in 37 female controls (0.8%; odds ratio [OR], 3.6; 95% CI, 2.6 to 5.1). The OR was higher for women with a first- or second-degree relative with breast cancer (OR, 5.0; 95% CI, 3.3 to 7.6) than for women with no family history (OR, 3.3; 95% CI, 2.3 to 4.7). If both a first- and second-degree relative were affected with breast cancer, the OR was 7.3 (95% CI, 3.2 to 16.8). Assuming a baseline risk of 6%, we estimate the lifetime risks for carriers of CHEK2 truncating mutations to be 20% for a woman with no affected relati...

Germline CHEK2 mutations in Jewish Ashkenazi women at high risk for breast cancer

PubMed, 2007

Background: Germline mutations in BRCA1 and BRCA2 genes account for only 20-40% of familial breast cancer cases. The CHEK2 gene encodes a checkpoint kinase, involved in response to DNA damage, and hence is a candidate gene for breast cancer susceptibility. Indeed, the CHEK2*1100delC truncating mutation was reported in a subset of mostly North European breast cancer families. The rate of the CHEK2*1100delC variant in the Ashkenazi Jewish population was reported to be 0.3%. Objectives: To evaluate whether CHEK2 germline mutations contribute to a breast cancer predisposition in Ashkenazi** Jewish high risk families. Methods: High risk Ashkenazi Jewish women, none of whom was a carrier of the predominant Jewish mutations in BRCA1/BRCA2, were genotyped for germline mutations in the CHEK2 gene by exon-specific polymerase chain reaction followed by denaturing gradient gel electrophoresis and sequencing of abnormally migrating fragments. Results: Overall, 172 high risk women were genotyped: 75 (43.6%) with breast cancer (average age at diagnosis 49.6 +/- 9.6 years, mean +/- SD) and 97 asymptomatic individuals (age at counseling 48.3 +/- 8.2 years). No truncating mutations were noted and four previously described missense mutations were detected (R3W 1.2%, 1157T 1.2%, R180C 0.6% and S428F 5%), one silent polymorphism (E84E 20.5%) and one novel missense mutation (Y424H 1.2%). Segregation analysis of the 1157T and S428F mutations (shown to affect protein function) with the cancer phenotype showed concordance for the CHK2*1157T mutation, as did two of three families with the CHK2*S428F mutation. Conclusions: CHEK2 missense mutations may contribute to breast cancer susceptibility in Ashkenazi Jews.

The breast cancer low-penetrance allele 1100delC in the CHEK2 gene is not present in Spanish familial breast cancer population

International Journal of Cancer, 2004

Searching for low-penetrance genes involved in breast cancer susceptibility has been a field of interest in the last few years. Recently, the CHEK 2 gene, involved in DNA damage and replication checkpoints, has been pointed out as a good candidate; moreover, a specific variant in this gene,1100delC, has been found to increase breast cancer susceptibility among familial breast cancer cases not attributable to mutations in BRCA1 or BRCA2 genes. In our present study, we evaluated the role of the 1100delC variant as a susceptibility allele in breast cancer in the Spanish population. However, our results suggest that this variant is absent or very infrequent in our population, making its screening irrelevant from the practical point of view. © 2003 Wiley-Liss, Inc.