Gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS): a new autosomal dominant syndrome.

OBJECTIVE: The purpose of this study was the clinical and pathological characterisation of a new autosomal dominant gastric polyposis syndrome, gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS). METHODS: Case series were examined, documenting GAPPS in three families from Australia, the USA and Canada. The affected families were identified through referral to centralised clinical genetics centres. RESULTS: The report identifies the clinical and pathological features of this syndrome, including the predominant dysplastic fundic gland polyp histology, the exclusive involvement of the gastric body and fundus, the apparent inverse association with current Helicobacter pylori infection and the autosomal dominant mode of inheritance. CONCLUSIONS: GAPPS is a unique gastric polyposis syndrome with a significant risk of gastric adenocarcinoma. It is characterised by the autosomal dominant transmission of fundic gland polyposis, including areas of dysplasia or intestinal-type gastric adenocarcinoma, restricted to the proximal stomach, and with no evidence of colorectal or duodenal polyposis or other heritable gastrointestinal cancer syndromes.

Targeted prostate cancer screening in men with mutations in BRCA1 and BRCA2 detects aggressive prostate cancer: preliminary analysis of the results of the IMPACT study.

OBJECTIVE: To evaluate the role of targeted prostate cancer screening in men with BRCA1 or BRCA2 mutations, an international study, IMPACT (Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted screening in BRCA1/2 mutation carriers and controls), was established. This is the first multicentre screening study targeted at men with a known genetic predisposition to prostate cancer. A preliminary analysis of the data is reported. PATIENTS AND METHODS: Men aged 40-69 years from families with BRCA1 or BRCA2 mutations were offered annual prostate specific antigen (PSA) testing, and those with PSA > 3 ng/mL, were offered a prostate biopsy. Controls were men age-matched (± 5 years) who were negative for the familial mutation. RESULTS: In total, 300 men were recruited (205 mutation carriers; 89 BRCA1, 116 BRCA2 and 95 controls) over 33 months. At the baseline screen (year 1), 7.0% (21/300) underwent a prostate biopsy. Prostate cancer was diagnosed in ten individuals, a prevalence of 3.3%. The positive predictive value of PSA screening in this cohort was 47·6% (10/21). One prostate cancer was diagnosed at year 2. Of the 11 prostate cancers diagnosed, nine were in mutation carriers, two in controls, and eight were clinically significant. CONCLUSIONS: The present study shows that the positive predictive value of PSA screening in BRCA mutation carriers is high and that screening detects clinically significant prostate cancer. These results support the rationale for continued screening in such men.

Treatment-focused DNA testing for newly diagnosed breast cancer patients: some implications for clinical practice.

There is accumulating evidence that women with breast cancer due to a familial BRCA1 or BRCA2 mutation benefit from specific surgical and chemotherapeutic treatment strategies. However, the rapid identification of such patients during the acute phase of treatment raises a number of issues. This study investigated Australian opinion leaders' views on the issues arising from such 'treatment-focused' genetic testing. Semi-structured interviews with 34 opinion leaders working in cancer genetics were undertaken. Interviewees acknowledged the introduction of treatment-focused DNA testing has the potential to positively transform the management of breast cancer patients, but were concerned that certain ethical and logistical issues have yet to be addressed. These include decision-making and consent, the familial nature of genetic information, and the management of genetics services within familial cancer clinics in the public hospital system in Australia. Service providers will need to have policies and strategies for managing the increased demand. It will also be necessary to include genetic counseling services within familial cancer clinics in the care pathway for newly diagnosed patients prior to any DNA testing to determine adjuvant treatment; such services may be more cost-effective than expecting surgeons and medical oncologists to fulfill this role.

A new DNA marker tightly linked to the fragile X locus (FRAXA).

The fragile X syndrome is the most common cause of familial mental retardation. Genetic counseling and gene isolation are hampered by a lack of DNA markers close to the disease locus. Two somatic cell hybrids that each contain a human X chromosome with a breakpoint close to the fragile X locus have been characterized. A new DNA marker (DXS296) lies between the chromosome breakpoints and is the closest marker to the fragile X locus yet reported. The Hunter syndrome gene, which causes iduronate sulfatase deficiency, is located at the X chromosome breakpoint that is distal to this new marker, thus localizing the Hunter gene distal to the fragile X locus.

Issues faced by unaffected men with a family history of prostate cancer: a multidisciplinary overview.

PURPOSE: Despite the established importance of the role of family history in prostate cancer, relatively little research encompasses the psychosocial issues relevant to unaffected men with a family history of prostate cancer. To determine the completeness and quality of available literature on the issues faced by men with a high risk of prostate cancer, we conducted a multidisciplinary review of the literature to provide some guidance on the information that clinicians might provide to men who are concerned about family history. MATERIALS AND METHODS: A structured literature search was conducted by a multidisciplinary team of clinicians and researchers who reviewed the medical and psychosocial literature, and identified 21 relevant studies. RESULTS: Research suggests that many high risk patients are concerned about the risk of prostate cancer, and some may significantly overestimate that risk. Several studies have shown high screening rates among high risk patients and high levels of interest in genetic testing for prostate cancer risk should it become available, yet many men also report a desire for more information about their personal risk and risk management options. CONCLUSIONS: Given the lack of clear data on the efficacy of prostate cancer screening among high risk patients, clinicians could consider providing men who are concerned about family history with information on their personal risk, help them to clarify the potential benefits, limitations and harms of prostate cancer screening in their situation, and then support their choice regarding the management of prostate cancer risk.

Management of MUTYH-associated neoplasia in Australia.

BACKGROUND: Mutations in the MUTYH gene, which codes for a base excision repair protein, have recently been found to cause an autosomal recessive syndrome characterized by multiple colorectal adenomas and increased risk of colorectal cancer. To identify key areas for clinical research, it is necessary to understand the current management of MUTYH-associated neoplasia. METHODS: Twelve questionnaires were sent to experts from familial colorectal cancer services throughout Australia, including representatives from all Australian states. The questionnaire was designed to clarify the practical management of MUTYH-associated neoplasia in the patient and their family. RESULTS: All 12 questionnaires were returned. For patients with fewer than 100 colorectal adenomas, and no dominant family history of colorectal neoplasia, most respondents carried out MUTYH testing before or concomitantly with APC. Australian laboratories generally carried out an initial directed analysis of the MUTYH gene for the two common mutations Y165C and G382D. For patients with biallelic MUTYH mutations all respondents endorsed regular colonoscopy surveillance with an interval of 1-2 years, whereas the recommended surveillance for monoallelic mutation carriers varied. CONCLUSION: This is the first study to document current management practices for MUTYH-associated neoplasia and forms a basis for the development of evidence-based recommendations as further research becomes available. Current guidelines for testing and management of MUTYH-associated neoplasia are discussed.

Letting the family know: balancing ethics and effectiveness when notifying relatives about genetic testing for a familial disorder.

OBJECTIVE: To increase the awareness among at risk relatives of the availability of genetic testing for a familial disorder while respecting their autonomy and privacy. METHODS: This was a comparison of preintervention and postintervention cohorts of families carried out in a state wide clinical service providing genetic counselling and testing for people at risk of familial adult onset cancer. Unaffected relatives who were not clients of the service in 74 kindreds with familial mutations causing familial breast and ovarian cancer, hereditary non-polyposis colorectal cancer, or Cowden syndrome were included in the study. In the baseline cohort (41 kindreds), family members who were clients of the clinical service and had been shown to be carriers of mutations were asked to advise relatives that genetic testing was available. In the intervention cohort (33 kindreds), the clinical service obtained consent to advise at risk relatives by letter that genetic testing was available. The main outcome measures were: (a) proportion of unaffected first and second degree relatives of the proband in each family whose genetic status was clarified within 2 years of the mutation being identified in the family, and (b) concerns regarding privacy and autonomy voiced by relatives receiving these letters. RESULTS: In the baseline cohort, the average proportion of relatives in each family whose genetic status was clarified was 23%. In the intervention cohort, the average proportion of relatives in each family whose genetic status was clarified was 40% (p = 0.001). None of the relatives in the intervention cohort complained of a breach of privacy or autonomy. CONCLUSION: Clinical services can take an effective and proactive approach to notifying relatives who are not their clients of the availability of genetic testing without compromising principles of privacy and autonomy.

Arteriovenous malformations in Cowden syndrome.

Cowden syndrome (OMIM No 158350) is a pleomorphic, autosomal dominant syndrome characterised by hamartomas in tissues derived from the endoderm, mesoderm, and ectoderm. It is caused by germline mutations in the PTEN gene and is allelic to the Bannayan-Riley-Ruvalcaba and Lhermitte-Duclos syndromes. The three syndromes are defined on clinical grounds but there is overlap in their definitions. The clinical features include trichilemmomas, verrucose lesions of the skin, macrocephaly, intellectual disability, cerebellar gangliocytoma, thyroid adenomas, fibroadenomas of the breast, and hamartomatous colonic polyps. Cutaneous haemangiomas are occasionally noted. Malignancies often arise in the affected tissues. Visceral arteriovenous malformations are a recognised component of the Bannayan-Riley-Ruvalcaba syndrome but have been reported rarely in Cowden syndrome. A family is described with a clinical diagnosis of Cowden syndrome, a familial frameshift mutation in the PTEN gene, and large visceral arteriovenous malformations. The association of these pleomorphic syndromes with arteriovenous malformations can be explained by the putative role of the PTEN gene in suppressing angiogenesis. Recognition of arteriovenous malformations as a clinical feature of Cowden syndrome has implications for the clinical management of patients with this disorder.

Intention to undergo prophylactic bilateral mastectomy in women at increased risk of developing hereditary breast cancer.

PURPOSE: To assess intention to undergo prophylactic bilateral mastectomy and psychologic determinants in unaffected women at increased risk of developing hereditary breast cancer. PATIENTS AND METHODS: Three hundred thirty-three women who were awaiting their initial appointments for risk assessment, advice about surveillance, and prophylactic options at one of 14 familial cancer clinics participated in a cross-sectional, questionnaire-based survey. RESULTS: Nineteen percent of women would consider and 47% would not consider a prophylactic mastectomy, should genetic testing identify a mutation in a breast cancer-predisposing gene, whereas 34% were unsure and 1% had already undergone a prophylactic mastectomy. In a bivariate analysis, women at a moderately increased risk of developing breast cancer had the highest proportion of subjects reporting that they would consider a prophylactic mastectomy (25%), compared with women at high risk (16%) (chi(2) = 7.79; P =.051). In multivariate analyses, consideration of prophylactic mastectomy strongly correlated with high levels of breast cancer anxiety (odds ratio [OR] = 17.4; 95% confidence interval [CI], 4.35 to 69.71; P =. 0001) and overestimation of one's breast cancer risk (OR = 3.01; 95% CI, 1.43 to 6.32; P =.0036), whereas there was no association with objective breast cancer risk (P =.60). CONCLUSION: A significant proportion of women at increased risk of developing hereditary breast cancer would consider prophylactic mastectomy. Although prophylactic mastectomy may be appropriate in women at high risk of developing breast cancer, it is perhaps less so in those who have a moderately increased risk. Such moderate-risk women are likely to benefit from interventions aimed at reducing breast cancer anxiety and correcting exaggerated breast cancer risk perceptions.

Ratio of male to female births in the offspring of BRCA1 and BRCA2 carriers.

A recent report based on 68 families, including 17 with mutations in BRCA1, suggested that there was an excess of female offspring born to BRCA1 mutation carriers. We have examined the gender ratio among offspring of 511 mutation carriers from 116 BRCA1 families, 77 and 39 from Australia and the United States, respectively. We found no evidence for a significant deviation from the expected proportion of female offspring in the Australian pedigrees, but there was an excess of female offspring in pedigrees from the USA. Ascertainment bias probably explains this bias, rather than a link with X-chromosome inactivation as previously suggested, because the families from the USA were ascertained for the purposes of linkage studies whereas those from Australia were ascertained through Familial Cancer Clinics to which they had been referred for clinical genetic counseling and mutation testing.

Sorting nexin 3 (SNX3) is disrupted in a patient with a translocation t(6;13)(q21;q12) and microcephaly, microphthalmia, ectrodactyly, prognathism (MMEP) phenotype.

A patient with microcephaly, microphthalmia, ectrodactyly, and prognathism (MMEP) and mental retardation was previously reported to carry a de novo reciprocal t(6;13)(q21;q12) translocation. In an attempt to identify the presumed causative gene, we mapped the translocation breakpoints using fluorescence in situ hybridisation (FISH). Two overlapping genomic clones crossed the breakpoint on the der(6) chromosome, locating the breakpoint region between D6S1594 and D6S1250. Southern blot analysis allowed us to determine that the sorting nexin 3 gene (SNX3) was disrupted. Using Inverse PCR, we were able to amplify and sequence the der(6) breakpoint region, which exhibited homology to a BAC clone that contained marker D13S250. This clone allowed us to amplify and sequence the der(13) breakpoint region and to determine that no additional rearrangement was present at either breakpoint, nor was another gene disrupted on chromosome 13. Therefore, the translocation was balanced and SNX3 is probably the candidate gene for MMEP in the patient. However, mutation screening by dHPLC and Southern blot analysis of another sporadic case with MMEP failed to detect any point mutations or deletions in the SNX3 coding sequence. Considering the possibility of positional effect, another candidate gene in the vicinity of the der(6) chromosome breakpoint may be responsible for MMEP in the original patient or, just as likely, the MMEP phenotype in the two patients results from genetic heterogeneity.

A single nucleotide polymorphism in the 5' untranslated region of RAD51 and risk of cancer among BRCA1/2 mutation carriers.

RAD51 colocalizes with both BRCA1 and BRCA2, and genetic variants in RAD51 would be candidate BRCA1/2 modifiers. We searched for RAD51 polymorphisms by sequencing 20 individuals. We compared the polymorphism allele frequencies between female BRCA1/2 mutation carriers with and without breast or ovarian cancer and between population-based ovarian cancer cases with BRCA1/2 mutations to cases and controls without mutations. We discovered two single nucleotide polymorphisms (SNPs) at positions 135 g-->c and 172 g-->t of the 5' untranslated region. In an initial group of BRCA1/2 mutation carriers, 14 (21%) of 67 breast cancer cases carried a "c" allele at RAD51:135 g-->c, whereas 8 (7%) of 119 women without breast cancer carried this allele. In a second set of 466 mutation carriers from three centers, the association of RAD51:135 g-->c with breast cancer risk was not confirmed. Analyses restricted to the 216 BRCA2 mutation carriers, however, showed a statistically significant association of the 135 "c" allele with the risk of breast cancer (adjusted odds ratio, 3.2; 95% confidence limit, 1.4-40). BRCA1/2 mutation carriers with ovarian cancer were only about one half as likely to carry the RAD51:135 g-->c SNP. Analysis of the RAD51:135 g-->c SNP in 738 subjects from an Israeli ovarian cancer case-control study was consistent with a lower risk of ovarian cancer among BRCA1/2 mutation carriers with the "c" allele. We have identified a RAD51 5' untranslated region SNP that may be associated with an increased risk of breast cancer and a lower risk of ovarian cancer among BRCA2 mutation carriers. The biochemical basis of this risk modifier is currently unknown.

Fragile X syndrome and nephrogenic diabetes insipidus.

We describe a man with the fra(X) syndrome and nephrogenic diabetes insipidus. The disease loci for both conditions are in the region Xq27.3-q28. This is the first report of the fra(X) syndrome associated with another X-linked disorder. Analysis of DNA markers suggested that the association in this man was coincidental.

A non-syndromal form of X-linked mental retardation (XLMR) is linked to DXS14.

An analysis of the linkage of a non-syndromal form of X-linked mental retardation (MRX1) with a number of markers on the X chromosome was performed in a large pedigree. The affected males had moderate mental retardation; in all other clinical respects and cytogenetically they were normal. No recombinants were observed between the MRX1 gene and the marker DXS14 (p58.1) located at Xp11-cen (Z (max.) = 2.12 at theta = 0.00). Recombination was observed between the MRX1 gene and the markers DXS7 and DXYS1 which flank DXS14. This form of XLMR maps to the centromeric portion of the X-chromosome.

Ring chromosome 11 and café-au-lait spots.

We report on the segregation of a cytogenetically non-deleted ring chromosome 11 and café-au-lait spots in a family. This appears to be the largest inherited ring autosome yet reported.

Familial neuronal intranuclear inclusion disease with ubiquitin positive inclusions.

Female monozygotic twins developed upper and lower limb neurogenic weakness in their thirties, followed by cerebellar ataxia, dysarthria and death after an illness duration of about 20 years. Autopsy revealed pathological features typical of neuronal intranuclear inclusion disease (NIID) and positive ubiquitin immunostaining of the inclusions. Two adult sons of one of the twins have now developed an identical illness. This family provides strong evidence of an hereditary form of NIID.

Long-term outcomes of genetic counseling in women at increased risk of developing hereditary breast cancer.

This multicenter study evaluated the impact of genetic counseling in 218 women at risk of developing hereditary breast cancer. Women were assessed prior to counseling and 12-month post-counseling using self-administered, mailed questionnaires. Compared to baseline, breast cancer genetics knowledge was increased significantly at follow-up, and greater increases in knowledge were associated with educational level. Breast cancer anxiety decreased significantly from baseline to follow-up, and these decreases were associated with improvements in perceived risk. A significant decrease in clinical breast examination was observed at the 12-month follow-up. Findings suggest that women with a family history of breast cancer benefit from attending familial cancer clinics as it leads to increases in breast cancer genetics knowledge and decreases in breast cancer anxiety. The lowered rates of clinical breast examination indicate that the content of genetic counseling may need to be reviewed to ensure that women receive and take away the right message.

A second case of microcephaly, microphthalmia, ectrodactyly (split-foot) and prognathism (MMEP).

In 1993, Viljoen and Smart described a woman with ectrodactyly of the feet, midline facial cleft, microphthalmia, and mental retardation in association with a de novo chromosome 6;13 translocation. We present a man with similar features who had a normal karyotype.

Fronto-facio-nasal dysplasia.

Fronto-facio-nasal dysplasia is a rare cause of facial clefts. The syndrome is characterized by paramedian facial clefts which involve the nose and palpebral fissures resulting in defects of the alae nasi and blepharophimosis, lagophthalmos, and S-shaped palpebral fissures. In addition affected children have ocular malformations such as epibulbar dermoids and colobomata of the iris or optic disk and may have a posterior encephalocele; these features distinguish this condition from fronto-nasal dysplasia and early amnion rupture sequence. We describe a child with unilateral features. Unilateral craniofacial clefts are usually assumed to have a low recurrence risk. However, fronto-facio-nasal dysplasia is an autosomal recessive condition and must be considered in any child with paramedian facial clefts.

A distinctive syndrome of brachycephaly, deafness, cataracts and mental retardation.

A boy with brachycephaly without craniosynostosis, raised intracranial pressure, deafness, cataracts, and global developmental delay is described.