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Objective Male breast cancer (MBC) is rare. Information about breast cancer is usually designed for female patients. However, in males this disease and some side effects differ from its female counterpart. Therefore, there is a need for male‐specific information. The aim was to assess unmet information needs of (a) MBC patients and (b) health professionals. Methods Dutch MBC patients (diagnosed between 2011 and 2016 in 21 hospitals), patient advocates and partners were invited to participate in focus groups and/or complete a paper‐based questionnaire on information needs. In addition, an online questionnaire on information needs was sent to health professionals involved in MBC patient care. Results In three focus groups with MBC patients (N = 12) and partners (N = 2) the following unmet information themes were identified: patients' experiences/photographs, symptoms, (delay of) diagnosis, treatments, side effects, follow‐up, psychological impact/coping, genetics and family, research and raising awareness. 77 of 107 MBC patients (72%) completed the questionnaire: most patients lacked information about acute (65%) or late (56%) side effects, particularly sexual side effects. Among health professionals, 110 of 139 (79%) had searched for MBC‐related information, specifically: patient information, anti‐hormonal therapy, genetic testing, research, and psychosocial issues. Conclusions Unmet information needs in MBC patients and health professionals were identified. Specific information on MBC should be developed to improve timely diagnosis, quality of life, treatment, and survival. A targeted website is an ideal tool to meet these needs. Therefore, we integrated these results into a user‐centered design to develop an informative website, www.mannenmetborstkanker.nl.

Diagnostic Exome Sequencing in 100 Consecutive Patients With Both Epilepsy and Intellectual Disability Snoeijen-Schouwenaars FM, van Ool JS, Verhoeven JS, et al. Epilepsia. 2019;60(1):155-164. doi:10.1111/epi.14618. Epub December 7, 2018. PMID: 30525188.Objective:Epilepsy is highly prevalent among patients with intellectual disability (ID), and seizure control is often difficult. Identification of the underlying etiology in this patient group is important for daily clinical care. We assessed the diagnostic yield of whole-exome sequencing (WES). In addition, we evaluated which clinical characteristics influence the likelihood of identifying a genetic cause and we assessed the potential impact of the genetic diagnosis on (antiepileptic) treatment strategy.Methods:One hundred patients with both unexplained epilepsy and (borderline) ID (intelligence quotient ≤85) were included. All patients were evaluated by a clinical geneticist, a (pediatric) neurologist, and/or a specialist ID physician. Whole-exome sequencing analysis was performed in 2 steps. In step 1, analysis was restricted to the latest versions of ID and/or epilepsy gene panels. In step 2, exome analysis was extended to all genes (so-called full exome analysis). The results were classified according to the American College of Medical Genetics and Genomics guidelines. Results: In 58 patients, the diagnostic WES analysis reported one or more variant(s). In 25 of the 100 patients, these were classified as (likely) pathogenic, in 24 patients as variants of uncertain significance, and in the remaining patients the variant was most likely not related to the phenotype. In 10 (40%) of 25 patients with a (likely) pathogenic variant, the genetic diagnosis might have an impact on the treatment strategy in the future.Significance:This study illustrates the clinical diagnostic relevance of WES for patients with both epilepsy and ID. It also demonstrates that implementing WES diagnostics might have impact on the (antiepileptic) treatment strategy in this population. Confirmation of variants of uncertain significance in (candidate) genes may further increase the yield. Diagnostic Yield of Genetic Tests in Epilepsy: A Meta-Analysis and Cost-Effectiveness Study Sánchez Fernández I, Loddenkemper T, Gaínza-Lein M, Sheidley BR, Poduri A. Neurology. 2019. Epub ahead of print. pii: 10.1212/WNL.0000000000006850. doi:10.1212/WNL.0000000000006850. PMID: 30610098 Objective:To compare the cost-effectiveness of genetic testing strategies in patients with epilepsy of unknown etiology.Methods:This meta-analysis and cost-effectiveness study compared strategies involving 3 genetic tests: chromosomal microarray (CMA), epilepsy panel (EP) with deletion/duplication testing, and whole-exome sequencing (WES) in a cost-effectiveness model, using “no genetic testing”“ as a point of comparison.Results:Twenty studies provided information on the diagnostic yield of CMA (8 studies), EP (9 studies), and WES (6 studies). The diagnostic yield was highest for WES: 0.45 (95% confidence interval [CI]: 0.33-0.57; 0.32 [95% CI: 0.22-0.44] adjusting for potential publication bias), followed by EP: 0.23 (95% CI: 0.18-0.29) and CMA: 0.08 (95% CI: 0.06-0.12). The most cost-effective test was WES with an incremental cost-effectiveness ratio (ICER) of US$15 000/diagnosis. However, after adjusting for potential publication bias, the most cost-effective test was EP (ICER: US$15 848/diagnosis) followed by WES (ICER: US$34 500/diagnosis). Among combination strategies, the most cost-effective strategy was WES, then if nondiagnostic, EP, then if nondiagnostic, CMA (ICER: US$15 336/diagnosis); although adjusting for potential publication bias, the most cost-effective strategy was EP ± CMA ± WES (ICER: US$18 385/diagnosis). Although the cost-effectiveness of individual tests and testing strategies overlapped, CMA was consistently less cost-effective than WES and EP.Conclusion:Whole-exome sequencing and EP are the most cost-effective genetic tests for epilepsy. Our analyses support for a broad population of patients with unexplained epilepsy, starting with these tests. Although less expensive, CMA has lower yield, and its use as the first-tier test is thus not supported from a cost-effectiveness perspective.

In this study, we compared cancer patients preference for computerised (tablet/web-based) surveys versus paper. We also assessed whether the understanding of a cancer-related topic, pharmacogenomics is affected by the survey format, and examined differences in demographic and medical characteristics which may affect patient preference and understanding. Three hundred and four cancer patients completed a tablet-administered survey and another 153 patients completed a paper-based survey. Patients who participated in the tablet survey were questioned regarding their preference for survey format administration (paper, tablet and web-based). Understanding was assessed with a ‘direct’ method, by asking patients to assess their understanding of genetic testing, and with a ‘composite’ score. Patients preferred administration with tablet (71%) compared with web-based (12%) and paper (17%). Patients

Tensions in the field have emerged over how best to communicate to the public about genomic discoveries in an era of direct-to-consumer (DTC) DNA testing services available through the Internet. Concerns over what the psychological and behavioral response might be to a nuanced, multiplex risk message have spurred some to offer caution in communicating to the public about personalized risk until the necessary research has been completed on how to communicate effectively. The popularization of DTC testing services, along with a spreading Internet culture on transparency for personal data, may make ‘waiting to communicate’ a moot point. To steer communication efforts in the midst of increasing access to personal genomic information, a self-regulation framework is presented. The framework emphasizes the importance of presenting a coherent message in all communiqués about public health genomics. Coherence should be based on an evidence-based model of how the public processes information about health conditions and an emphasis on risk-to-action links. Recommendations from the President’s Council of Advisors for Science and Technology are reviewed as a way of identifying targets of opportunity for structured communications both within the healthcare system and in the broader external ecosystem of publicly available health information technologies.

The minimum prevalence of lethal Osteogenesis imperfecta type II, thanatophoric dysplasia and achondroplasia were derived following detailed case note review of all perinatal lethal skeletal dysplasias (SD) in Northern Ireland over a 12 year period. Multiple sources of ascertainment, including genetic notes, radiological reports and post mortem findings, were used. 39 cases were identified. Thanatophoric dysplasia was the commonest diagnosis made (22), followed by osteogenesis imperfecta type II (four children) and achondroplasia (two children). Eleven other diagnoses each occurred once in the 12 year period. The minimum prevalence range, per live births, of each of the common skeletal dysplasias in Northern Ireland has been calculated; thanatophoric dysplasia 0.80/10,000, osteogenesis imperfecta type II 0.15/10,000 and achondroplasia 0.07/10,000. The prevalence range for thanatophoric dysplasia is much higher than reported in previous studies. We discuss reasons for the prevalence figures obtained.

Wilson's disease (WD), an autosomal recessive disorder of copper transport, is one of the most common inherited metabolic disorders in Korea. Despite its frequency, the incidence and carrier frequency of WD has not yet been estimated in the Korean population. We therefore screened for four major missense mutations (p.Arg778Leu, p.Ala874Val, p.Leu1083Phe, and p.Asn1270Ser) of the ATP7B gene in 476 newborn filter papers by real-time multiplex PCR and melting curve analysis using the SYBR Green intercalator method based on the amplification refractory mutation system test. Newborn filter papers with abnormal melting curves were subjected to subsequent sequence analysis. Three mutated alleles, one p.Arg778Leu and two p.Ala874Val, were detected among the 476 newborn filter papers (952 alleles). The carrier frequency and incidence of WD in the Korean population were determined as 1 in 88.2 and 30,778, respectively, by reversely calculating based on the Hardy-Weinberg law.

The risk effect of APOE epsilon 4 allele for Alzheimer's disease is acknowledged, whereas the putative protective effect of epsilon 2 allele remains in debate.To investigate whether those inconsistent findings may be attributable to differences in age and sex composition of the study populations.A community dementia free cohort (n = 985) agedor =75 years was followed up to detect Alzheimer's disease cases (DSM-III-R criteria). Data were analysed using Cox models with adjustment for major potential confounders.Over a median 5.6 year follow up, Alzheimer's disease was diagnosed in 206 subjects. Compared with APOE epsilon 3/epsilon 3 genotype, the relative risk (RR) of Alzheimer's disease was 1.4 (95% confidence interval (CI), 1.0 to 2.0; p = 0.03) for heterozygous epsilon 4 allele and 3.1 (95% CI, 1.6 to 5.9) for homozygous epsilon 4 allele. The association between epsilon 4 allele and Alzheimer's disease risk was stronger in men than in women (RR related to the interaction term epsilon 4 allele by sex, 0.4; 95% CI, 0.2 to 0.9). The epsilon 4 allele accounted for one third of Alzheimer's disease cases among men, but only one tenth among women. The epsilon 2 allele was related to a reduced Alzheimer's disease risk mainly in people aged85 years (RR, 0.4; 95% CI, 0.2 to 0.8). The RR of Alzheimer's disease related to the interaction term of epsilon 2 allele by age was 2.4 (95% CI, 1.0 to 6.0; p = 0.06).The APOE genotype specific effects on Alzheimer's disease vary by age and sex, in which the epsilon 4 allele has a stronger risk effect in men, and the epsilon 2 allele confers a protective effect only in younger-old people.

Recent discoveries of trypsinogen and trypsin inhibitor mutations in patients with chronic pancreatitis (CP) support the hypothesis that an inappropriate activation of pancreatic zymogens to active enzymes within the pancreatic parenchyma starts the inflammatory process. Current data suggest that CP may be inherited dominant, recessive, or complex as a result of mutations in the above mentioned or yet unidentified genes. Evaluation of patients with CP should include genetic testing. Cystic fibrosis (CF) is an autosomal recessive inherited disorder caused by mutations in the CF transmembrane conductance regulator (CFTR) gene and is characterised by pancreatic insufficiency and chronic bronchopulmonary infection. The progression and severity of pulmonary disease differs considerably between people with identical CFTR mutations and does not seem to correlate with the type or class of the CFTR mutation. The identification of further disease modifying genetic factors will increase the pathophysiological understanding and may help to identify new therapeutic targets.

New insights into the genetic basis of disease are being generated at an ever increasing rate. This explosion of information was ignited by technological advances, such as the polymerase chain reaction and automated DNA sequencing. Although its promise is great, the integration of genetics into the everyday practice of medicine remains challenging. This review discusses the application of molecular genetics in general with a specific focus on hereditary diseases of the digestive organs. The application of molecular genetics in everyday clinical routine is hampered by the difficult interpretation of test results. These difficulties include the prediction of disease penetrance, the presence of multiple mutations of a particular gene with varying functional consequences, and the importance of exogenous factors modulating disease expression. To date, the most significant impact of genetics has been to increase our understanding of disease aetiology and pathogenesis and to reliably identify siblings of affected patients with the risk to develop symptomatic disease.

The three autosomal dominant inherited polyposis syndromes, familial adenomatous polyposis, juvenile polyposis, and Peutz-Jeghers polyposis predispose to colorectal cancer as does hereditary non-polyposis colorectal cancer syndrome. Uncovering the genetic background of these four cancer traits provides the possibility for genetic testing of the family members of an affected patient. Before testing identification of the underlying family specific pathogenic mutation is mandatory. This is possible in about 60% to 95% of families. Endoscopic surveillance can be safely discontinued in mutation negative family members and surveillance or prophylactic surgery can be targeted to mutation positive members alone. Testing requires genetic counselling and written informed consent to prevent misunderstanding and to minimise untoward effects such as anxiety. Permanent surveillance and adequate prophylactic treatment for all mutation positive subjects and families is best ensured in national or regional polyposis registries with the capacity to take care of long term follow up from generation to generation.

Classic CAH (salt-wasting and simple virilizing) meets all of the recommended criteria for newborn screening. There are reliable and efficient newborn screening tests, the disorder results in high morbidity and mortality if left undetected, there is effective treatment that reduces negative outcomes, and there is a relatively high incidence. When compared with the case findings without the benefit of screening, the data from screening programs show reduced adrenal crises, reduced incorrect sex assignments, and reduced deaths. Racial/ethnic prevalence differences are present in newborn screening program data. The Texas data indicate a lower disease frequency in African-Americans when compared with Caucasians, and international data indicate higher frequencies in native Yupik Eskimos, Brazilians, residents of La Reunion, and Filipinos. When worldwide clinical ascertainment data are compared with newborn screenng data, it is clear that newborns with CAH (especially males) die when screening is not done. To be effective in reducing mortality, newborn screening must be performed soon after birth, and the results must be available quickly so that early salt-wasting crises can be averted. It is preferable that newborn screening laboratiories be operational 7 days a week, and that sample delivery from the collection site to testing laboratory be as efficient as possible, including weekends and holidays, so that undue testing delays are not encountered. These two requirements pose major challenges for most programs, but they are critical to optimal screening outcome. Based on the studies in Texas, with second screening samples collected at approximately 2 weeks of age, some newborns with simple virilizing CAH are missed on initial screening using current testing protocols. There is need to set a screening cut-off such that the false-positive rate does not oversaturate the follow-up system, in part owing to the insensitivity of current kit methodologies and the biochemical manifestations of CAH. With advances in genetic testing procedures and improved automation techniques, it may soon be possible for CAH screening programs to include genotyping as a second-tier confirmation as a part of the newborn screening protocol. Despite the fact that CAH is a continuum of disorders, the correlation between genotype and phenotype is fairly consistent in most cases. For the purpose of screening, genotyping will likely be useful only for differential diagnoses of non-salt wasters, given the necessary time constraints and expense of obtaining genotypes and the need for immediate diagnosis/treatment of salt wasters. It is hoped that newborn screening programs will begin to provide answers to some of these question in addition to their primary function of reducing the morbidity and mortality resulting from CAH.

Carnitine palmitoyltransferase II (CPT II; EC 2.3.1.21), an enzyme associated with the inner mitochondrial membrane, is important in the transport of long-chain fatty acids from the cytosol into the mitochondrial matrix for β-oxidation (1). CPT II deficiency presents as three distinct clinical phenotypes: adult myopathic (MIM 255110), lethal neonatal (MIM 600649), and a severe infantile phenotype (2). The adult form is the most common lipid myopathy in humans and is characterized by muscle pain, stiffness, and myoglobinuria triggered by exercise, fasting, anesthesia, or other metabolic stressors (3). CPT II is a homotetramer (4) encoded by a gene (MIM 600650) on chromosome 1p32 (5) that spans 20 kb and contains five exons ranging in length from 81 to 1305 bp (6). At least 15 mutations in CPT2 are associated with the adult and infantile disorders (7)(8)(9). CPT II deficiency is an autosomal recessive disorder (3)(9); however, recent biochemical and molecular evidence suggests the existence of manifesting carriers, predicting that the prevalence of the disease may be even higher than previously believed (9). Screening for mutations in CPT2 has been performed using DNA isolated from biopsied muscle tissue (9), venous blood (10), lymphoblasts (11), or fibroblasts (8). Isolation of DNA from these specimens is time-consuming, and mutation screening generally has been performed using restriction fragment length polymorphisms (12) or allele-specific oligonucleotide (ASO) detection (9), requiring portions of several days for completion (9). Large-scale screening has not been performed to determine the carrier frequency of the common mutations in the general population. Although the methods for DNA isolation, PCR amplification, and ASO analysis developed previously by our laboratory are effective for detecting known mutations in the CPT2 gene (9), they were too costly and laborious for application to large family studies or population screening. We proposed …

Identification of low-income women with the rare but serious risk of hereditary cancer and their referral to appropriate services presents an important public health challenge. We report the results of formative research to reach thousands of women for efficient identification of those at high risk and expedient access to free genetic services. External validity is maximized by emphasizing intervention fit with the two end-user organizations who must connect to make this possible. This study phase informed the design of a subsequent randomized controlled trial.We conducted a randomized controlled pilot study (n = 38) to compare two intervention models for feasibility and impact. The main outcome was receipt of genetic counseling during a two-month intervention period. Model 1 was based on the usual outcall protocol of an academic hospital genetic risk program, and Model 2 drew on the screening and referral procedures of a statewide toll-free phone line through which large numbers of high-risk women can be identified. In Model 1, the risk program proactively calls patients to schedule genetic counseling; for Model 2, women are notified of their eligibility for counseling and make the call themselves. We also developed and pretested a family history screener for administration by phone to identify women appropriate for genetic counseling.There was no statistically significant difference in receipt of genetic counseling between women randomized to Model 1 (3/18) compared with Model 2 (3/20) during the intervention period. However, when unresponsive women in Model 2 were called after 2 months, 7 more obtained counseling; 4 women from Model 1 were also counseled after the intervention. Thus, the intervention model that closely aligned with the risk program's outcall to high-risk women was found to be feasible and brought more low-income women to free genetic counseling. Our screener was easy to administer by phone and appeared to identify high-risk callers effectively. The model and screener are now in use in the main trial to test the effectiveness of this screening and referral intervention. A validation analysis of the screener is also underway.Identification of intervention strategies and tools, and their systematic comparison for impact and efficiency in the context where they will ultimately be used are critical elements of practice-based research.

The clinical utility of genetic tests is determined by the outcomes following test use. Like other measures of value, it is often contested. Stakeholders may have different views about benefits and risks and about the importance of social versus health outcomes. They also commonly disagree about the evidence needed to determine whether a test is effective in achieving a specific outcome. Questions may be presented as factual disagreements, when they are actually debates about what information matters or how facts should be interpreted and used in clinical decision-making. Defining the different issues at stake is therefore an important element of policy-making. Key issues include evidence standards for test use, and in particular, the circumstances under which prospective controlled data should be required, as well as evidence on feasibility, cost and equitable delivery of testing; the goals of population-based screening programs, and in particular, the role of social outcomes in evaluating test value; and the appropriate uses and funding of tests that inform non-medical actions. Addressing each of these issues requires attention to stakeholder values and methods for effective deliberation that incorporate consumer as well as health professional perspectives.

Spinal muscular atrophy (SMA) is a common, often fetal, autosomal recessively inherited disease leading to progressive muscle wasting and paralysis as a result of degeneration of anterior horn cells of the spinal cord. The SMA-determining gene, called the survival of motor neuron gene (SMN), is present on 5q13 in two nearly identical copies, telomeric SMN (SMN1) and centromeric SMN (SMN2). It has been established that SMA is caused by mutations in SMN1 whereas homozygous deletion of SMN2 has apparently no pathological consequences. The aim of this study is to develop an easy and inexpensive method for the isolation of high-quality template DNA from blood samples for SMA carrier screening by multiplex polymerase chain reaction. We have developed a protocol that optimizes detection of the SMN1 copy number in the human genome, producing a specific and sensitive assay using DNA extracted from a dried blood spot on IsoCode paper.

Background: Prior to the discovery of the Huntington’s disease (HD) mutation, the prevalence, incidence, and new mutation rates for this disease were based on the presence of progressive choreic movements and a positive family history. Objective: To evaluate the uptake of the HD genetic analysis in Spain, and to provide additional information on the epidemiology of this disease from the experience of 9 years of direct genetic testing. Methods: From 1994 to 2002, CAG repeat length was determined in 317 patients with symptoms compatible with HD. In all cases, demographic, clinical, and family data were carefully reviewed. Results: HD diagnosis (CAG repeat length ⩾36) was confirmed in 166 (52%) symptomatic cases. Of these, 76 (45.8%) reported a positive family history and in 21 cases (12.7%) family history was negative. New mutation events were genetically proven in three families and highly suspected in another, estimating that the minimum new mutation rate for HD in our population is >4%, with a potential mutation rate of 8%. More than 16% of all HD cases had late onset (>59 years) of symptoms, and in three quarters of these the family history was negative. The incidence rate for the autonomous communities of Navarra and the Basque country, based on the number of newly diagnosed cases by genetic testing, was 4.7 per million per year. Conclusions: Direct HD genetic testing shows that the incidence and mutation rates of the disease are 2–3 times higher than previously reported. We also demonstrated the relevance of CAG repeat length assessment in diagnosing patients with late onset of symptoms and negative family history for HD.

Background: In familial intracranial aneurysms there is evidence for genetic heterogeneity, probably from mutations at separate loci. Objectives: To compare demographic and clinical features in patients of families with familial intracranial aneurysm and different patterns of inheritance; and to compare the ages of patients with subarachnoid haemorrhage (SAH) in affected parent–child pairs to determine whether there is anticipation. Methods: Pedigrees for 53 families with familial intracranial aneurysms were constructed, divided into patterns of inheritance suggestive or not suggestive of autosomal dominant transmission. Demographic and clinical features were compared. The age at time of SAH in affected parent–child pairs was compared using the Wilcoxon test. Results: No differences in demographic or clinical features were found between families compatible with an autosomal dominant pattern of inheritance and those with a non-dominant pattern. In families with affected members in two successive generations the age at time of SAH in parents was 55.2 years and in children 35.4 years (mean difference, 19.8 years, p

Objectives: We report here the clinical and genetic features of two new families with autosomal dominant progressive external ophthalmoplegia (adPEO). Patients and methods: The examination of index patients included a detailed clinical characterisation, histological analysis of muscle biopsy specimens, and genetic testing of mitochondrial and nuclear DNA extracted from muscle and leucocytes. Results: Index patients in both families presented with PEO and developed other clinical disease manifestations, such as myopathy and cardiomyopathy (patient 1) and axonal neuropathy, diabetes mellitus, hearing loss, and myopathy (patient 2), later in the course of illness. Both patients had ragged red fibres on muscle histology. Southern blot of mtDNA from muscle of patient 2 showed multiple deletions. In this case, a novel heterozygous missense mutation F485L was identified in the nuclear encoded putative mitochondrial helicase Twinkle. The mutation co-segregated with the clinical phenotype in the family and was not detected in 150 control chromosomes. In the other index patient, sequencing of ANT1, C10orf2 (encoding for Twinkle), and POLG1 did not reveal pathogenic mutations. Conclusions: Our cases illustrate the clinical variability of adPEO, add a novel pathogenic mutation in Twinkle (F485L) to the growing list of genetic abnormalities in adPEO, and reinforce the relevance of other yet unidentified genes in mtDNA maintenance and pathogenesis of adPEO.

The purpose of this study was to develop a quantifiable method to fix 6-n-propylthiouracil (PROP) onto filter paper disks and to test the validity of the method relative to the three-solution test, previously developed in this laboratory. Filter paper disks were impregnated with 50 mmol/l PROP or 1.0 mol/l NaCl then dried. The concentration of PROP per disk was determined to be 0.280 mg+/-2.2% (CV) by ethanol extraction. Subjects were studied in two groups (n=62 per group). All subjects were initially classified by the three-solution test and then were independently classified by the paper disk test. In the paper disk test, group means for PROP (+/-95% confidence interval) were calculated and used to establish numerical cutoff scores for taster group classification. Cutoff scores for Group 1 were used to classify subjects in Group 2, verifying that the cutoffs were applicable to another subject group. The percentage of nontasters, medium tasters, and supertasters identified by paper disk was 27%, 42%, and 31%, respectively, which is consistent with expected frequencies in the population. For Group 1, the agreement between the two classification methods ranged from 86% to 94% across taster groups. For Group 2, the agreement ranged from 83% to 100%. The contingency coefficient (P) of the degree of association between the two classification methods was high (P=0.77 and P=0.74 for Groups 1 and 2, respectively; P< or =.001). These results demonstrate that the paper disk method is a reliable screening tool for assessing sensitivity to PROP that has numerous applications in basic and applied research.

Iron is an important component of the Earth's crust, but its own chemistry greatly limits utilisation and also sets the basis for its toxicity. The capacity of readily exchanging electrons in aerobic conditions makes iron essential for fundamental cell functions, such as DNA synthesis, transport of oxygen and electrons, and cell respiration. On the other hand, as humans have no means to control iron excretion, excess iron, regardless of the route of entry, accumulates in parenchymal organs and threatens cell viability. In fact, a number of disease states (that is, iron overload diseases) attributable to genetic or acquired factors are pathogenetically linked to excess body iron stores and iron removal therapy is an effective lifesaving strategy in such circumstances.

Amplification of DNA from whole blood collected on Guthrie card filter paper presents considerable technical obstacles due to the presence of natural PCR inhibitors (protein, heavy metals, heme, and heme degradation products) and low copy number of genomic material. For this purpose we evaluated guanidine thiocyanate‐impregnated filter paper (GT‐903), a DNA collection device designed specifically to bind PCR inhibitors and preserve DNA in an aqueous extractable form. Compared to standard 903, which retains DNA and elutes inhibitors during aqueous extraction, we found GT‐903 retained 90% of protein, hemoglobin, and iron. SDS‐PAGE analysis indicated that the majority of the protein released from standard 903 corresponded to albumin (70‐) and globin (15‐kDa); negligible levels of these proteins were eluted from GT‐903. To evaluate PCR efficiency, we amplified the 491 bp region encoding the cystic fibrosis ΔF508 mutation. Using comparable template, we found GT‐903 amplification more efficient than standard 903 following qualitative (TBE‐PAGE) and quantitative (anti‐dsDNA EIA) determination. We conclude that GT‐903 provides a good DNA collection device and addresses the complications associated with natural PCR inhibitors. J. Clin. Lab. Anal. 11:87–93. © 1997 Wiley‐Liss, Inc.