BackgroundCurrent knowledge of the aetiology of hereditary breast cancer in the four main South African population groups (black, coloured, Indian and white) is limited. Risk assessments in the black, coloured and Indian population groups are challenging because of restricted information regarding the underlying genetic contributions to inherited breast cancer in these populations. We focused this study on premenopausal patients (diagnosed with breast cancer before the age of 50; n = 78) and triple negative breast cancer (TNBC) patients (n = 30) from the four South African ethnic groups. The aim of this study was to determine the frequency and spectrum of germline mutations in BRCA1, BRCA2 and PALB2 and to evaluate the presence of the CHEK2 c.1100delC allele in these patients.MethodsIn total, 108 South African breast cancer patients underwent mutation screening using a Next-Generation Sequencing (NGS) approach in combination with Multiplex Ligation-dependent Probe Amplification (MLPA) to detect large rearrangements in BRCA1 and BRCA2.ResultsIn 13 (12 %) patients a deleterious mutation in BRCA1/2 was detected, three of which were novel mutations in black patients. None of the study participants was found to have an unequivocal pathogenic mutation in PALB2. Two (white) patients tested positive for the CHEK2 c.1100delC mutation, however, one of these also carried a deleterious BRCA2 mutation. Additionally, six variants of unknown clinical significance were identified (4 in BRCA2, 2 in PALB2), all in black patients. Within the group of TNBC patients, a higher mutation frequency was obtained (23.3 %; 7/30) than in the group of patients diagnosed before the age of 50 (7.7 %; 6/78).ConclusionThis study highlights the importance of evaluating germline mutations in major breast cancer genes in all of the South African population groups. This NGS study shows that mutation analysis is warranted in South African patients with triple negative and/or in premenopausal breast cancer.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-015-1913-6) contains supplementary material, which is available to authorized users.

Background. Germline pathogenic mutations in cancer susceptibility genes result in inherited cancer syndromes. In the Afrikaner population of South Africa (SA), three founder mutations in the BRCA genes that lead to hereditary breast and ovarian cancer syndrome (HBOCS) have been identified. Objectives. To investigate the uptake and type of molecular testing performed on patients for HBOCS, to determine the prevalence of the three Afrikaner founder BRCA mutations as well as non-founder BRCA mutations in the study population, and to analyse the utility of two mutation prediction models (Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) and Manchester scoring method) in assisting with the decision for the most cost-effective testing option. Methods. A retrospective file review was performed on counsellees of self-reported Afrikaner ancestry from Johannesburg, SA (2001 -2014), with a personal or family history of breast and/or ovarian cancer. Demographic and family history information was recorded and Manchester and BOADICEA scores were calculated for each patient. Results. Of 86 unrelated counsellees whose files were reviewed, 54 (62.8%) underwent BRCA genetic testing; 18 (33.3%) tested positive for a mutation, and 14 of these (77.8%) for an Afrikaner founder mutation. Twelve counsellees had the BRCA2 c.7934delG mutation. Four non-founder mutations were identified. BOADICEA scores were significantly higher in counsellees who tested positive for a mutation than in those who tested negative. Conclusions. Founder mutation testing should be performed as a first-line option. BOADICEA is very useful in identifying counsellees at high risk for a BRCA mutation and also assists with the decision to pursue further testing following a negative founder mutation result. These findings assist in guiding an informed genetic counselling service for at-risk individuals with an Afrikaner background.

Childhood genetic conditions impact not only the child who is diagnosed but also the day-to-day lives of all members of a family. However, our understanding of the perspectives and needs of unaffected adolescents in families affected by rare genetic conditions is limited. To address this gap, we conducted semi-structured interviews with 10 participants aged 14-20 years, all of whom had a sibling with a rare genetic condition. An interpretive description approach was used to develop a framework that described how participants' experiences of having a sibling with a rare genetic condition shaped the formation of their identity. This experience influenced identity formation both directly, and indirectly through four other phenomena: (1) normalization, of both their own experiences and their siblings' differences; (2) knowledge seeking, regarding their sibling's condition and what uncertainties remained; (3) caretaking, which limited some opportunities and was associated with uncertainty around the future; and (4) social experience, including their relationship with their affected sibling, with their peers, and with the rest of their family participants felt that they were isolated and lacked appropriate supports. The results of this study can help to inform a family-centered approach to genetic counseling and highlight the importance of tailored supports for this population.

As uptake of rapid genome sequencing (GS) in the neonatal period steadily increases, a clinical genetics service that is optimized to the needs of parents becomes increasingly important. We aimed to investigate factors that influence decision making about rapid GS by parents of infants admitted to neonatal intensive care units (NICU) and explore their experiences of decisional conflict and anxiety during this time. Parents of neonates suspected of having a genetic disorder and offered rapid GS in the NICU completed a questionnaire measuring experience with GS counseling, decisional conflict, and anxiety level. Our results demonstrate that despite a largely positive GS experience (70%; 21/30) among the survey respondents, 50.0% (14/28) experienced moderate to severe anxiety measured using the GAD‐7 scale, and 34.6% (9/26) experienced decisional conflict measured using the SURE scale. We also showed that prematurity may be a modifier of anxiety in this group of parents and although not statistically significant, distance lived away from the hospital site could have practical significance. Open‐ended responses to survey questions highlighted that feeling overwhelmed, the types of engagements parents had with healthcare providers, and the timing of information provision also influenced parental decision making in this setting. We suggest that the GAD‐7 scale for generalized anxiety and SURE scale for decisional conflict could be incorporated by genetic counselors into routine care of parents of neonates who have been offered rapid GS to identify those who may need additional support (resources, information, or psychological). These tools may inform ways that communication between patients and providers can be improved and enhanced and clinical genetics services in the NICU can be optimized. We suggest that integrating genetic counselors into the NICU care team could increase access for this population and ensure delivery of optimized patient education and counseling.

Fanconi anaemia (FA) is a genotypically and phenotypically heterogeneous genetic condition, characterized cytogenetically by chromosomal instability and breakage secondary to impaired DNA repair mechanisms. Affected individuals typically manifest growth restriction and congenital physical abnormalities and most progress to hematological disease including bone marrow aplasia. A rare genetic subtype of FA (FA-D1) is caused by biallelic mutations in the BRCA2 gene. Affected individuals manifest severe congenital anomalies and significant pigmentary changes and are additionally at risk for early onset leukemia and certain solid organ malignancies, including Wilms tumors and brain tumors. Parents of affected individuals are obligate carriers for heterozygous BRCA2 mutations and are thus potentially at risk for adult onset cancers which fall within the hereditary breast and ovarian cancer spectrum. We present two cases of black South African patients with FA diagnosed with biallelic BRCA2 mutations and discuss the phenotypic consequences and implications for them and their families. Recognition of this severe end of the phenotypic spectrum of FA is critical in allowing for confirmation of the diagnosis as well as cascade screening and appropriate care of family members.

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Background. Fanconi anaemia (FA) is an autosomal recessive, genetically heterogeneous disorder, characterised by interstrand crosslinkinduced chromosome breaks, congenital abnormalities and predisposition to malignancies. It has a prevalence of about 1/40 000 in black South Africans (SAs). A founder mutation in the FANCG gene occurs in the homozygous state in 77.5% of southern African blacks. Objective. To locate additional pathogenic mutations in the FANCG gene of black FA patients who were heterozygous for the founder mutation. Methods. Further mutation analysis of the FANCG gene was undertaken in 7 patients clinically suspected of having FA. The parents of two of the patients were tested for the presence of the founder mutation to determine true heterozygosity in the patients. To clarify whether or not previously unreported variants were pathogenic, 58 random black SA individuals were screened. Results. Three novel single base pair deletions, resulting in frameshift mutations (c.247delA, c.179delT and c.899delT) were identified in 3/7 patients. A fourth patient was found to have a single base substitution resulting in a splice site mutation (c.1636+1G>A). The remaining three patients were not found to harbour any pathogenic mutations. Two non-pathogenic variants were also identified among the seven patients. Conclusion. The results of this small sample suggest that a second common mutation in the FANCG gene is unlikely in this population. However, FANCG sequencing should be performed on patients heterozygous for the common founder mutation to attempt to confirm their diagnosis.

Overall, 3.3% of black South Africans with POAG have a Gly374Val or Tyr453del MYOC mutation. The Tyr453del mutation is incompletely penetrant. That the mutation is necessary but insufficient introduces a counseling dilemma. Mutation screening can, however, identify high-risk individuals who can be monitored to detect early signs of the disease. The Gly374Val mutation is predicted to be damaging to MYOC. The Lys500Arg mutation is predicted to be benign and tolerated. This study has important implications for the management and counseling of black South African patients with POAG and their families.