Germline loss-of-function mutations in LZTR1 predispose to an inherited disorder of multiple schwannomas

Constitutional SMARCB1 mutations at 22q11.23 have been found in ∼50% of familial and <10% of sporadic schwannomatosis cases. We sequenced highly conserved regions along 22q from eight individuals with schwannomatosis whose schwannomas involved somatic loss of one copy of 22q, encompassing SMARCB1 and NF2, with a different somatic mutation of the other NF2 allele in every schwannoma but no mutation of the remaining SMARCB1 allele in blood and tumor samples. LZTR1 germline mutations were identified in seven of the eight cases. LZTR1 sequencing in 12 further cases with the same molecular signature identified 9 additional germline mutations. Loss of heterozygosity with retention of an LZTR1 mutation was present in all 25 schwannomas studied. Mutations segregated with disease in all available affected first-degree relatives, although four asymptomatic parents also carried an LZTR1 mutation. Our findings identify LZTR1 as a gene predisposing to an autosomal dominant inherited disorder of multiple schwannomas in ∼80% of 22q-related schwannomatosis cases lacking mutation in SMARCB1.

A 3-year randomized therapeutic trial of nitisinone in alkaptonuria

Alkaptonuria is a rare, autosomal recessive disorder of tyrosine degradation due to deficiency of the third enzyme in the catabolic pathway. As a result, homogentisic acid (HGA) accumulates and is excreted in gram quantities in the urine, which turns dark upon alkalization. The first symptoms, occurring in early adulthood, involve a painful, progressively debilitating arthritis of the spine and large joints. Cardiac valvular disease and renal and prostate stones occur later. Previously suggested therapies have failed to show benefit, and management remains symptomatic. Nitisinone, a potent inhibitor of the second enzyme in the tyrosine catabolic pathway, is considered a potential therapy; proof-of-principle studies showed 95% reduction in urinary HGA. Based on those findings, a prospective, randomized clinical trial was initiated in 2005 to evaluate 40 patients over a 36-month period. The primary outcome parameter was hip total range of motion with measures of musculoskeletal function serving as secondary parameters. Biochemically, this study consistently demonstrated 95% reduction of HGA in urine and plasma over the course of 3 years. Clinically, primary and secondary parameters did not prove benefit from the medication. Side effects were infrequent. This trial illustrates the remarkable tolerability of nitisinone, its biochemical efficacy, and the need to investigate its use in younger individuals prior to development of debilitating arthritis.

Use of nitisinone in patients with alkaptonuria

Alkaptonuria, a rare autosomal recessive disorder caused by mutations in the HGD gene and deficiency of homogentisate 1,2 dioxygenase, is characterized by ochronosis, arthritis, and daily excretion of gram quantities of homogentisic acid (HGA). Nitisinone, an inhibitor of the enzyme 4-hydroxyphenylpyruvate dioxygenase, can drastically reduce urinary excretion of HGA in individuals with alkaptonuria. We investigated the safety and the HGA-depleting efficacy of nitisinone in an open-label, single-center study of 9 alkaptonuria patients (5 women, 4 men; 35-69 years of age) over the course of 3 to 4 months. Each patient received nitisinone in incremental doses, 0.35 mg bid followed by 1.05 mg bid, and remained on this dosage and a regular diet for 3 months. Nitisinone reduced urinary HGA levels from an average of 4.0 +/- 1.8 (SD) g/day to 0.2 +/- 0.2 g/day ( P < .001). The average plasma tyrosine concentration, initially 68 +/- 18 mmicro mol/L, rose to 760 +/- 181 micro mol/L ( P < .001). During the final week of the study, 5 patients adhered to a protein-restricted diet (40 g/day), and their mean plasma tyrosine level fell from 755 +/- 167 to 603 +/- 114 mu mol/L. Six of the 7 patients who received nitisinone for more than 1 week reported decreased pain in their affected joints. Weekly ophthalmologic examinations showed no signs of corneal toxicity. Adverse events included the passing of kidney stones, the recognition of symptoms related to aortic stenosis, and elevation of liver transaminase levels. We conclude that low-dose nitisinone effectively reduced urinary HGA levels in patients with alkaptonuria. Future long-term clinical trials are planned to determine the benefits of nitisinone in preventing joint deterioration and providing pain relief, and its long-term side effects.

Mouse screen reveals multiple new genes underlying mouse and human hearing loss

Adult-onset hearing loss is very common, but we know little about the underlying molecular pathogenesis impeding the development of therapies. We took a genetic approach to identify new molecules involved in hearing loss by screening a large cohort of newly generated mouse mutants using a sensitive electrophysiological test, the auditory brainstem response (ABR). We review here the findings from this screen. Thirty-eight unexpected genes associated with raised thresholds were detected from our unbiased sample of 1,211 genes tested, suggesting extreme genetic heterogeneity. A wide range of auditory pathophysiologies was found, and some mutant lines showed normal development followed by deterioration of responses, revealing new molecular pathways involved in progressive hearing loss. Several of the genes were associated with the range of hearing thresholds in the human population and one, SPNS2, was involved in childhood deafness. The new pathways required for maintenance of hearing discovered by this screen present new therapeutic opportunities.

Mutation spectrum of homogentisic acid oxidase (HGD) in alkaptonuria

Alkaptonuria (AKU) is a rare autosomal recessive metabolic disorder, characterized by accumulation of homogentisic acid, leading to darkened urine, pigmentation of connective tissue (ochronosis), joint and spine arthritis, and destruction of cardiac valves. AKU is due to mutations in the homogentisate dioxygenase gene (HGD) that converts homogentisic acid to maleylacetoacetic acid in the tyrosine catabolic pathway. Here we report a comprehensive mutation analysis of 93 patients enrolled in our study, as well as an extensive update of all previously published HGD mutations associated with AKU. Within our patient cohort, we identified 52 HGD variants, of which 22 were novel. This yields a total of 91 identified HGD variations associated with AKU to date, including 62 missense, 13 splice site, 10 frameshift, 5 nonsense, and 1 no-stop mutation. Most HGD variants reside in exons 3, 6, 8, and 13. We assessed the potential effect of all missense variations on protein function, using five bioinformatic tools specifically designed for interpretation of missense variants (SIFT, POLYPHEN, PANTHER, PMUT, and SNAP). We also analyzed the potential effect of splice-site variants using two different tools (BDGP and NetGene2). This study provides valuable resources for molecular analysis of alkaptonuria and expands our knowledge of the molecular basis of this disease.

The duplication 17p13.3 phenotype: analysis of 21 families delineates developmental, behavioral and brain abnormalities, and rare variant phenotypes

Chromosome 17p13.3 is a gene rich region that when deleted is associated with the well-known Miller-Dieker syndrome. A recently described duplication syndrome involving this region has been associated with intellectual impairment, autism and occasional brain MRI abnormalities. We report 34 additional patients from 21 families to further delineate the clinical, neurological, behavioral, and brain imaging findings. We found a highly diverse phenotype with inter- and intrafamilial variability, especially in cognitive development. The most specific phenotype occurred in individuals with large duplications that include both the YWHAE and LIS1 genes. These patients had a relatively distinct facial phenotype and frequent structural brain abnormalities involving the corpus callosum, cerebellar vermis, and cranial base. Autism spectrum disorders were seen in a third of duplication probands, most commonly in those with duplications of YWHAE and flanking genes such as CRK. The typical neurobehavioral phenotype was usually seen in those with the larger duplications. We did not confirm the association of early overgrowth with involvement of YWHAE and CRK, or growth failure with duplications of LIS1. Older patients were often overweight. Three variant phenotypes included cleft lip/palate (CLP), split hand/foot with long bone deficiency (SHFLD), and a connective tissue phenotype resembling Marfan syndrome. The duplications in patients with clefts appear to disrupt ABR, while the SHFLD phenotype was associated with duplication of BHLHA9 as noted in two recent reports. The connective tissue phenotype did not have a convincing critical region. Our experience with this large cohort expands knowledge of this diverse duplication syndrome.

Expanding the genotypic and phenotypic spectrum in a diverse cohort of 104 individuals with Wiedemann-Steiner syndrome

Wiedemann-Steiner syndrome (WSS) is an autosomal dominant disorder caused by monoallelic variants in KMT2A and characterized by intellectual disability and hypertrichosis. We performed a retrospective, multicenter, observational study of 104 individuals with WSS from five continents to characterize the clinical and molecular spectrum of WSS in diverse populations, to identify physical features that may be more prevalent in White versus Black Indigenous People of Color individuals, to delineate genotype-phenotype correlations, to define developmental milestones, to describe the syndrome through adulthood, and to examine clinicians' differential diagnoses. Sixty-nine of the 82 variants (84%) observed in the study were not previously reported in the literature. Common clinical features identified in the cohort included: developmental delay or intellectual disability (97%), constipation (63.8%), failure to thrive (67.7%), feeding difficulties (66.3%), hypertrichosis cubiti (57%), short stature (57.8%), and vertebral anomalies (46.9%). The median ages at walking and first words were 20 months and 18 months, respectively. Hypotonia was associated with loss of function (LoF) variants, and seizures were associated with non-LoF variants. This study identifies genotype-phenotype correlations as well as race-facial feature associations in an ethnically diverse cohort, and accurately defines developmental trajectories, medical comorbidities, and long-term outcomes in individuals with WSS.

Two novel CHS1 (LYST) mutations: clinical correlations in an infant with Chediak-Higashi syndrome

Chediak-Higashi syndrome (CHS) is a rare autosomal recessive disease characterized by variable degrees of oculocutaneous albinism, recurrent infections, and a mild bleeding tendency, with late neurologic dysfunction. Most patients also undergo an accelerated phase of lymphohistiocytosis and die at an early age unless they receive an allogeneic hematopoietic stem cell transplant (SCT). Mutations in the CHS1 (LYST) gene result in CHS. Here, we describe an adopted infant who is compound heterozygous for two novel CHS1 gene mutations, both of which are predicted to result in truncated proteins. The two mutations are a nonsense mutation (c.1540 C>T, CGA>TGA, R514X) in exon 5 and a one base pair deletion (del c.9893T, F3298fsX3304) in exon 43, coding for part of the CHS1 protein's BEACH domain. These two newly described mutations are expected to give rise to a severe phenotype and, indeed, the patient had absolutely no cytotoxicity by natural killer cells or cytotoxic lymphocytes prior to his allogeneic SCT.

Aortic stenosis and vascular calcifications in alkaptonuria

Alkaptonuria is a rare metabolic disorder of tyrosine catabolism in which homogentisic acid (HGA) accumulates and is deposited throughout the spine, large joints, cardiovascular system, and various tissues throughout the body. In the cardiovascular system, pigment deposition has been described in the heart valves, endocardium, pericardium, aortic intima and coronary arteries. The prevalence of cardiovascular disease in patients with alkaptonuria varies in previous reports. We present a series of 76 consecutive adult patients with alkaptonuria who underwent transthoracic echocardiography between 2000 and 2009. A subgroup of 40 patients enrolled in a treatment study underwent non-contrast CT scans and these were assessed for vascular calcifications. Six of the 76 patients had aortic valve replacement. In the remaining 70 patients, 12 patients had aortic sclerosis and 7 patients had aortic stenosis. Unlike degenerative aortic valve disease, we found no correlation with standard cardiac risk factors. There was a modest association between the severity of aortic valve disease and joint involvement, however, we saw no correlation with urine HGA levels. Vascular calcifications were seen in the coronaries, cardiac valves, aortic root, descending aorta and iliac arteries. These findings suggest an important role for echocardiographic screening of alkaptonuria patients to detect valvular heart disease and cardiac CT to detect coronary artery calcifications.

Minocycline-induced hyperpigmentation masquerading as alkaptonuria in individuals with joint pain

Alkaptonuria, a rare autosomal-recessive disorder caused by mutations in the HGD gene and a deficiency of homogentisate 1,2-dioxygenase, is characterized by accumulation of homogentisic acid (HGA), ochronosis, and destruction of connective tissue resulting in joint disease. Certain medications have been reported to cause cutaneous hyperpigmentation resembling that of alkaptonuria. We present 5 such cases. Eighty-eight patients with a possible diagnosis of alkaptonuria were examined at the National Institutes of Health Clinical Center between June 2000 and March 2004. The diagnosis of alkaptonuria was confirmed or ruled out by measurement of HGA in the urine. Five patients with findings consistent with ochronosis, including pigmentary changes of the ear and mild degenerative disease of the spine and large joints, were diagnosed clinically as having alkaptonuria, but the diagnosis was withdrawn based on normal urine HGA levels. All 5 patients were women who had taken minocycline for dermatologic or rheumatologic disorders for extended periods. Minocycline-induced hyperpigmentation should be considered in the differential diagnosis of ochronosis. This could be of increased significance now that minocycline and other tetracyclines have been proposed as therapeutic options for rheumatoid arthritis, bringing a new population of patients with ochronosis and arthritis to medical attention with the potential, but incorrect, diagnosis of alkaptonuria.

Dysregulation of the NRG1/ERBB pathway causes a developmental disorder with gastrointestinal dysmotility in humans

Hirschsprung disease (HSCR) is the most frequent developmental anomaly of the enteric nervous system, with an incidence of 1 in 5000 live births. Chronic intestinal pseudo-obstruction (CIPO) is less frequent and classified as neurogenic or myogenic. Isolated HSCR has an oligogenic inheritance with RET as the major disease-causing gene, while CIPO is genetically heterogeneous, caused by mutations in smooth muscle-specific genes. Here, we describe a series of patients with developmental disorders including gastrointestinal dysmotility, and investigate the underlying molecular bases. Trio-exome sequencing led to the identification of biallelic variants in ERBB3 and ERBB2 in 8 individuals variably associating HSCR, CIPO, peripheral neuropathy, and arthrogryposis. Thorough gut histology revealed aganglionosis, hypoganglionosis, and intestinal smooth muscle abnormalities. The cell type-specific ErbB3 and ErbB2 function was further analyzed in mouse single-cell RNA sequencing data and in a conditional ErbB3-deficient mouse model, revealing a primary role for ERBB3 in enteric progenitors. The consequences of the identified variants were evaluated using quantitative real-time PCR (RT-qPCR) on patient-derived fibroblasts or immunoblot assays on Neuro-2a cells overexpressing WT or mutant proteins, revealing either decreased expression or altered phosphorylation of the mutant receptors. Our results demonstrate that dysregulation of ERBB3 or ERBB2 leads to a broad spectrum of developmental anomalies, including intestinal dysmotility.

Neonatal intrahepatic cholestasis caused by citrin deficiency: prevalence and SLC25A13 mutations among Thai infants

Background

The most common causes of cholestatic jaundice are biliary atresia and idiopathic neonatal hepatitis (INH). Specific disorders underlying INH, such as various infectious and metabolic causes, including neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) especially, in East Asian populations are increasingly being identified. Since most NICCD infants recovered from liver disease by 1 year of age, they often are misdiagnosed with INH, leading to difficulty in determining the true prevalence of NICCD. Mutation(s) of human SLC25A13 gene encoding a mitochondrial aspartate/glutamate carrier isoform 2 (AGC2), can lead to AGC2 deficiency, resulting in NICCD and an adult-onset fatal disease namely citrullinemia type II (CTLN2). To study the prevalence of NICCD and SLC25A13 mutations in Thai infants, and to compare manifestations of NICCD and non-NICCD, infants with idiopathic cholestatic jaundice or INH were enrolled. Clinical and biochemical data were reviewed. Urine organic acid and plasma amino acids profiles were analyzed. PCR-sequencing of all 18 exons of SLC25A13 and gap PCR for the mutations IVS16ins3kb and Ex16+74_IVS17-32del516 were performed. mRNA were analyzed in selected cases with possible splicing error.

Results

Five out of 39 (12.8%) unrelated infants enrolled in the study were found to have NICCD, of which three had homozygous 851del4 (GTATdel) and two compound heterozygous 851del4/IVS16ins3kb and 851del4/1638ins23, respectively. Two missense mutations (p.M1? and p.R605Q) of unknown functional significance were identified. At the initial presentation, NICCD patients had higher levels of alkaline phosphatase (ALP) and alpha-fetoprotein (AFP) and lower level of alanine aminotransferase (ALT) than those in non-NICCD patients (p< 0.05). NICCD patients showed higher citrulline level and threonine/serine ratio than non-NICCD infants (p< 0.05). Fatty liver was found in 2 NICCD patients. Jaundice resolved in all NICCD and in 87.5% of non-NICCD infants at the median age of 9.5 and 4.0 months, respectively.

Conclusion

NICCD should be considered in infants with idiopathic cholestasis. The preliminary estimated prevalence of NICCD was calculated to be 1/48,228 with carrier rate of 1/110 among Thai infants. However, this number may be underestimated and required further analysis with mutation screening in larger control population to establish the true prevalence of NICCD and AGC2 deficiency.

Molecular analysis of the iduronate-2-sulfatase gene in Thai patients with Hunter syndrome

Molecular defects in the gene encoding the enzyme iduronate-2-sulfatase (IDS) result in Hunter disease (mucopolysaccharidosis type II, MPS II). To determine the molecular basis of MPS II in Thailand, the IDS gene was analysed in 20 Thai patients with Hunter syndrome from 18 unrelated families. A total of 19 different mutations, including 9 missense mutations, 3 nonsense mutations, 3 splice site alterations, 1 deletion, 2 indels, and 1 rearrangement were identified, 8 of which were novel (p.R101C, p.D148V, p.G224A, p.K227E, p.E254X, p.W337X, c.440_442delinsTT and c.720_731delinsTTTCAGATGTTCTCCCCAG). Evaluation of the IDS activity of two hemizygous variants identified in the same patient, p.R101C and p.R468Q, by expression of IDS with the individual mutations in COS 7 cells indicated that only the p.R468Q mutation affected IDS protein activity. Two exonic mutations, c.257C>T (p.P86L) and c.418G>A, were found to activate multiple cryptic splice sites, resulting in aberrantly spliced transcripts. Thus, MPS II in Thailand is caused by a diverse set of defects affecting both IDS protein production and activity.

Outcome of infants diagnosed with 3-methyl-crotonyl-CoA-carboxylase deficiency by newborn screening

INTRODUCTION

3-Methyl CoA carboxylase (3-MCC) deficiency is an inborn error of metabolism in the catabolism of the amino acid leucine. Original reports suggested this disorder was associated with significant neurological and biochemical effects. However newborn screening has identified a higher than expected incidence of this disorder with apparent normal outcome in most cases.

METHOD

A retrospective analysis of thirty-five cases of 3-MCC deficiency identified by newborn screening and diagnosed by enzyme or molecular analysis.

RESULTS

There was a strong inverse correlation between initial C5OH level and residual enzyme activity. A few reports of hypoglycemia, ketosis, poor feeding/failure to thrive or fasting intolerance were reported, but there was no clear relationship between symptoms and residual enzyme activity. Developmental outcome included several children with mental retardation (including one with Down syndrome and one with schizencephaly) and two with Autism Spectrum disorders but there was no apparent relationship to residual enzyme activity. Free carnitine deficiency was relatively common.

DISCUSSION

Although residual enzyme activity was clearly related to metabolite elevation, there was no apparent relationship with other measures of outcome. The number of reports of neurologic abnormalities or metabolic symptoms (poor feeding, hypoglycemia, fasting intolerance, etc.) is concerning, but the significance is unclear in this retrospective sample.

Dominant-negative heterozygous mutations in AIRE confer diverse autoimmune phenotypes

Autoimmune polyendocrine syndrome type 1 (APS-1) is an autosomal recessive disease characterized by severe and childhood onset organ-specific autoimmunity caused by mutations in the autoimmune regulator (AIRE) gene. More recently, dominant-negative mutations within the PHD1, PHD2, and SAND domains have been associated with an incompletely penetrant milder phenotype with later onset familial clustering, often masquerading as organ-specific autoimmunity. Patients with immunodeficiencies or autoimmunity where genetic analyses revealed heterozygous AIRE mutations were included in the study and the dominant-negative effects of the AIRE mutations were functionally assessed in vitro. We here report additional families with phenotypes ranging from immunodeficiency, enteropathy, and vitiligo to asymptomatic carrier status. APS-1-specific autoantibodies can hint to the presence of these pathogenic AIRE variants although their absence does not rule out their presence. Our findings suggest functional studies of heterozygous AIRE variants and close follow-up of identified individuals and their families.

CSNK2B: A broad spectrum of neurodevelopmental disability and epilepsy severity

CSNK2B has recently been implicated as a disease gene for neurodevelopmental disability (NDD) and epilepsy. Information about developmental outcomes has been limited by the young age and short follow-up for many of the previously reported cases, and further delineation of the spectrum of associated phenotypes is needed. We present 25 new patients with variants in CSNK2B and refine the associated NDD and epilepsy phenotypes. CSNK2B variants were identified by research or clinical exome sequencing, and investigators from different centers were connected via GeneMatcher. Most individuals had developmental delay and generalized epilepsy with onset in the first 2 years. However, we found a broad spectrum of phenotypic severity, ranging from early normal development with pharmacoresponsive seizures to profound intellectual disability with intractable epilepsy and recurrent refractory status epilepticus. These findings suggest that CSNK2B should be considered in the diagnostic evaluation of patients with a broad range of NDD with treatable or intractable seizures.

Molecular characterization of type 3 (neuronopathic) Gaucher disease in Thai patients

Gaucher disease is an autosomal recessive lysosomal storage disorder due to deficiency of the lysosomal enzyme glucocerebrosidase. Three clinical phenotypes, type 1, nonneuronopathic; and types 2 and 3, acute and subacute neuronopathic are recognized. The incidence of Gaucher disease in the Thai population is unknown, but likely under-diagnosed. We performed molecular analysis in four patients, from three sibships, with type 3 Gaucher disease. Four mutant glucocerebrosidase (GBA) alleles were identified including two novel splice site mutations, IVS6-1G>C and IVS9-3C>G; both are predicted to result in truncated protein products, p.F255fsX256, and p.K464fsX487 and p.S463fsX480, respectively. One patient, homozygous for the L444P point mutation, had a "Norbottnian-like" phenotype, with more severe visceral involvement, kyphosis, barreled chest, and no neurological involvement other than supranuclear gaze palsy. These molecular studies of neuronopathic Gaucher disease will provide additional genotype-phenotype correlation particularly in non-Caucasian population.

Screening and Preventative Strategies for Patients at High Risk for Breast Cancer

PURPOSE

Current US guidelines recommend more intensive breast cancer screening and preventive strategies for patients at more than 20% lifetime risk for breast and ovarian cancer (high risk for breast and ovarian cancer [HRBOC]). Guidelines recommend that yearly mammograms alternating with magnetic resonance imaging (MRI) screening should be considered as early as 30 years old. Furthermore, BRCA mutation carriers should consider bilateral mastectomy and bilateral oophorectomy after age 35. It was unclear what the uptake of screening and risk-reducing strategies were for patients who were cancer-free and cancer survivors seen by Kaiser Permanente Mid-Atlantic States (KPMAS) Genetics.

METHODS

We retrospectively studied female patients (members of KPMAS between 2005 and 2016) diagnosed as HRBOC and/or tested for breast cancer-related mutations by KPMAS Genetics during 2013-2016. We identified cancer diagnoses, mammogram and breast MRI screening, mastectomies, and oophorectomies that occurred before and after the Genetics visit during the study period.

RESULTS

Our cohort included 813 women with a HRBOC diagnosis, with a median 51 years of age at diagnosis, 45% White, 38% Black, and 15% other ethnicity. Most cancers occurred prior to the Genetics visit: 513/527 breast cancer diagnoses and 55/57 ovarian cancer diagnoses. Fewer than five prophylactic mastectomies and 89 prophylactic oophorectomies were identified. Among 228 patients who were 30-75 years old, breast cancer-free at the time of HRBOC diagnosis, and members for over 6 months, 190 (83%) had at least one screening test (mammogram or MRI) after the consultation with Genetic, but 79% never had an MRI before or after the consultation.

CONCLUSION

Our findings suggest that earlier detection of patients with HRBOC and closer monitoring is needed.

Feasibility and Assessment of a Cascade Traceback Screening Program (FACTS): Protocol for a Multisite Study to Implement and Assess an Ovarian Cancer Traceback Cascade Testing Program

Ovarian cancer (OVCA) patients may carry genes conferring cancer risk to biological family; however, fewer than one-quarter of patients receive genetic testing. "Traceback" cascade testing -outreach to potential probands and relatives-is a possible solution. This paper outlines a funded study (U01 CA240747-01A1) seeking to determine a Traceback program's feasibility, acceptability, effectiveness, and costs. This is a multisite prospective observational feasibility study across three integrated health systems. Informed by the Conceptual Model for Implementation Research, we will outline, implement, and evaluate the outcomes of an OVCA Traceback program. We will use standard legal research methodology to review genetic privacy statutes; engage key stakeholders in qualitative interviews to design communication strategies; employ descriptive statistics and regression analyses to evaluate the site differences in genetic testing and the OVCA Traceback testing; and assess program outcomes at the proband, family member, provider, system, and population levels. This study aims to determine a Traceback program's feasibility and acceptability in a real-world context. It will account for the myriad factors affecting implementation, including legal issues, organizational- and individual-level barriers and facilitators, communication issues, and program costs. Project results will inform how health care providers and systems can develop effective, practical, and sustainable Traceback programs.

Mitochondrial DNA mutations in a patient with sex reversal and clinical features consistent with Fraser syndrome

We describe a 20-year-old 46,XY woman, with clinical findings of Fraser syndrome and three mitochondrial DNA (mtDNA) mutations of Leber hereditary optic neuropathy. The patient had microphthalmia, blindness, widely spaced nipples, bifid ureter, syndactyly of the toes, and mental retardation. Sonography showed the presence of a uterus and intra-abdominal gonads. The proband was screened for mtDNA mutations because of chronic gastrointestinal pseudo-obstruction, urinary tract dysmotility, seizures, mental retardation and persistent macrocytosis, as well as the intermittent elevation of methylmalonic acid. Analysis of point mutations by multiplex polymerase chain reaction and allele-specific oligonucleotide dot-blot hybridization revealed three homoplasmic mtDNA mutations, T14484C, T4216C, and T3394C. This represents a unique case with sex reversal, Fraser-like syndrome, and mitochondrial disease.

Abstract P4-10-13: Screening and risk reducing surgeries for patients at high risk for breast and ovarian cancer at an integrated care setting

Background: Current US guidelines recommend more intensive screening and preventive strategies for patients with a known pathogenic germline mutation or a high lifetime risk based on breast cancer risk prediction models. The American Cancer Society, for example, recommends that yearly mammogram alternating with MRI screening should be considered as early as 30 years old in women with a lifetime breast cancer risk of &gt; 20%. Furthermore, NCCN recommends that BRCA1/2 mutation carriers consider additional risk-reducing strategies, including bilateral mastectomy, bilateral oophorectomy at age 35, or post-child bearing, and hormonal chemoprevention. It is unclear what the uptake of screening and risk reducing strategies are after an HRBROC assessment and recommendations by Genetics at an integrated care setting.

Methods: We retrospectively studied female patients diagnosed as high risk for breast and ovarian cancer (HRBOC) (regardless of prior cancer) and/or tested for BRCA mutations by a genetic counselor or physician geneticist at Kaiser Permanente Mid-Atlantic States (KPMAS) Genetics clinics between 2005-2016. We identified cancer diagnoses, mammogram and MRI screening, mastectomies and oophorectomies with ICD diagnosis or CPT procedure codes during the study period. We defined prophylactic mastectomy or prophylactic oophorectomy as occurring either 180 days prior to, or without a diagnosis of breast or ovarian cancer respectively. We assessed screening with a mammogram or MRI, post Genetics visit for patients 30-75yrs old at time of HRBOC dx, and had no breast cancer prior to, or within 180 days, of the Genetics visit.

Results: Our cohort included 813 women with a HRBOC diagnosis, with a median 51 yrs of age at diagnosis, 45% White, 38% Black and 15% other race. Since genetics services for cancer at KPMAS were established recently, 98% of visits occurred after 1-1-2013. Table 1 shows the distribution of cancer diagnoses and surgeries pre and post Genetics visit. 249 Breast cancer-free patients were screened post Genetic visit between mid-2013-2016: 159 (64%) had at least 1 screening test, 68 had two to three and only 3 women had four to six screening tests. The median time to the latest screen after HRBOC dx was 14.4 mo, (range 2 days to 39 mo). Post-Genetics screening frequency did not differ by race.

Conclusion: The majority of women visited Genetics after a diagnosis of breast or ovarian cancer. Patients received prophylactic oophorectomies more often than prophylactic mastectomies. Screening in cancer free patients with a HRBROC diagnosis appears to be limited to 1-3 screens post diagnostic visit. Our findings suggest that earlier detection of patients at high risk for breast and ovarian cancer and closer monitoring is needed.

Table 1.Cancer diagnoses and Surgeries Pre and Post Genetics Visit for HRBROC (2004-2016) (N=813) pre-Geneticspost-GeneticsTotalBreast Cancer diagnosed51314527Post cancer Mastectomy3198327Prophylactic Mastectomy314Ovarian Cancer diagnosed55257Post cancer oophorectomy40343Prophylactic oophorectomy632689

Citation Format: Ter-Minassian M, Visvanathan K, Jefferson CR, Schaeffer ML, Suwannarat P. Screening and risk reducing surgeries for patients at high risk for breast and ovarian cancer at an integrated care setting [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-10-13.