Links between gender norms and the intergenerational transmission of health information in parents carrying BRCA1/2 pathogenic variants

Understanding how gender norms affect parents' communication of genetic and cancer risk information to their children can enable healthcare professionals to better facilitate cascade genetic testing. We conducted a qualitative study with semi-structured interviews to determine social factors associated with parents carrying the BRCA1/2 pathogenic variants who communicated cancer prevention practices to their children. Thirty adult carriers (23 women, 7 men) participated in the interviews. All had at least one child aged over 8 years old. Interview topics included their discovery of the variants, their relationship to their body and to the risk of cancer, as well as disclosure to and subsequent communication with their children after testing positive for BRCA1/2. The interviews were analyzed qualitatively, and the major themes identified were identified and compared. We described the roles played by the BRCA1/2 carriers and their partners in communicating cancer prevention practices to their children, from how they managed their own risk of cancer after testing positive, to how they disclosed the risks linked to these pathogenic variants to their children. We also described their involvement in the process of their children going for professional genetic consultation. Gender norms lead women to be more attentive than men to their own health and that of their loved ones. In the context of the transmission of genetic information to children, gender differences in behavior are reinforced by perceptions of the risks of BRCA1/2 variants and women's related health management practices. Cancer prevention is shaped by complex links between gender norms and health management practices.

Association of PHB 1630 C>T and MTHFR 677 C>T polymorphisms with breast and ovarian cancer risk in BRCA1/2 mutation carriers: results from a multicenter study

BACKGROUND

The variable penetrance of breast cancer in BRCA1/2 mutation carriers suggests that other genetic or environmental factors modify breast cancer risk. Two genes of special interest are prohibitin (PHB) and methylene-tetrahydrofolate reductase (MTHFR), both of which are important either directly or indirectly in maintaining genomic integrity.

METHODS

To evaluate the potential role of genetic variants within PHB and MTHFR in breast and ovarian cancer risk, 4102 BRCA1 and 2093 BRCA2 mutation carriers, and 6211 BRCA1 and 2902 BRCA2 carriers from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2 (CIMBA) were genotyped for the PHB 1630 C>T (rs6917) polymorphism and the MTHFR 677 C>T (rs1801133) polymorphism, respectively.

RESULTS

There was no evidence of association between the PHB 1630 C>T and MTHFR 677 C>T polymorphisms with either disease for BRCA1 or BRCA2 mutation carriers when breast and ovarian cancer associations were evaluated separately. Analysis that evaluated associations for breast and ovarian cancer simultaneously showed some evidence that BRCA1 mutation carriers who had the rare homozygote genotype (TT) of the PHB 1630 C>T polymorphism were at increased risk of both breast and ovarian cancer (HR 1.50, 95%CI 1.10-2.04 and HR 2.16, 95%CI 1.24-3.76, respectively). However, there was no evidence of association under a multiplicative model for the effect of each minor allele.

CONCLUSION

The PHB 1630TT genotype may modify breast and ovarian cancer risks in BRCA1 mutation carriers. This association need to be evaluated in larger series of BRCA1 mutation carriers.

The TP53 Arg72Pro and MDM2 309G>T polymorphisms are not associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers

Background:

The TP53 pathway, in which TP53 and its negative regulator MDM2 are the central elements, has an important role in carcinogenesis, particularly in BRCA1- and BRCA2-mediated carcinogenesis. A single nucleotide polymorphism (SNP) in the promoter region of MDM2 (309T>G, rs2279744) and a coding SNP of TP53 (Arg72Pro, rs1042522) have been shown to be of functional significance.

Methods:

To investigate whether these SNPs modify breast cancer risk for BRCA1 and BRCA2 mutation carriers, we pooled genotype data on the TP53 Arg72Pro SNP in 7011 mutation carriers and on the MDM2 309T>G SNP in 2222 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analysed using a Cox proportional hazards model within a retrospective likelihood framework.

Results:

No association was found between these SNPs and breast cancer risk for BRCA1 (TP53: per-allele hazard ratio (HR)=1.01, 95% confidence interval (CI): 0.93–1.10, P_trend=0.77; MDM2: HR=0.96, 95%CI: 0.84–1.09, P_trend=0.54) or for BRCA2 mutation carriers (TP53: HR=0.99, 95%CI: 0.87–1.12, P_trend=0.83; MDM2: HR=0.98, 95%CI: 0.80–1.21, P_trend=0.88). We also evaluated the potential combined effects of both SNPs on breast cancer risk, however, none of their combined genotypes showed any evidence of association.

Conclusion:

There was no evidence that TP53 Arg72Pro or MDM2 309T>G, either singly or in combination, influence breast cancer risk in BRCA1 or BRCA2 mutation carriers.

[Hereditary predispositions to gynaecological cancers]

The breast, ovary and endometrial cancers are hereditary in 5 to 10% of the cases. These genetic predisposition syndromes can be classified into two major classes: ovarian cancer and breast cancer predisposition family cases (genes BRCA1 and BRCA2) and family cases of colon cancer, endometrial cancer and ovarian cancer (Lynch syndrome or HNPCC) (genes hMLH1, hMSH2, hMLH6). The estimate of the family and individual risk can contribute in a determining manner to the management of these patients, by the practice of screening or an adapted prevention. Indeed, the risk of cancer of an individual having a positive test for a gene of predisposition to breast cancer (BRCA1, BRCA2) or to the colon cancer (hMLH1, hMSH2, hMLH6) lies between 50 and 70% at the age of 70 years. The indication of a genetic test must be discussed within the framework of an oncogenetic consultation. An individual and family medical management ranging from simple monitoring to prophylactic surgery is proposed to these predisposed people.

Structural and numerical aberrations of chromosome 22 in a case of follicular variant of papillary thyroid carcinoma revealed by conventional and molecular cytogenetics

This study reports a case of papillary carcinoma with vesicular components showing multiclonal aberrations of chromosome 22 as revealed by RHG-banding cytogenetics and by fluorescence in situ hybridization (FISH; whole chromosome 22 and BCR-ABL-specific locus probes, multi-FISH). Four clones with chromosome 22 changes as the sole abnormality were seen. The main abnormal clone lacked the whole chromosome 22. A del(22)(q11) was observed in a second group of cells. The third clone had an idic(22). Finally, FISH revealed a fourth abnormal cell population with a der(17)t(?17;22). Some of these chromosome 22 alterations have been described in other solid tumors such as meningiomas and neurinomas, suggesting a common genetic pathway of tumor progression occurring in a multistep process. Chromosome 22 changes do not seem to be involved in pure papillary thyroid tumors and therefore could be related to the maintenance of a follicular-type histological pattern.