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The objective of this study is to review ethical and clinical guidelines and position papers concerning the presymptomatic and predictive genetic testing of minors. The databases Medline, Philosopher's Index, Biological Abstracts, Web of Science and Google Scholar were searched using keywords relating to the presymptomatic and predictive testing of children. We also searched the websites of the national bioethics committees indexed on the websites of World Health Organization (WHO) and the German Reference Centre for Ethics in the Life Sciences, the websites of the Human Genetics Societies of various nations indexed on the website of the International Federation of Human Genetics Societies and related links and the national medical associations indexed on the website of the World Medical Association. We retrieved 27 different papers dealing with guidelines or position papers that fulfilled our search criteria. They encompassed the period 1991-2005 and originated from 31 different organizations. The main justification for presymptomatic and predictive genetic testing was the direct benefit to the minor through either medical intervention or preventive measures. If there were no urgent medical reasons, all guidelines recommend postponing testing until the child could consent to testing as a competent adolescent or as an adult. Ambiguity existed for childhood-onset disorders for which preventive or therapeutic measures are not available and for the timing of testing for childhood-onset disorders. Although the guidelines covering presymptomatic and predictive genetic testing of minors agree strongly that medical benefit is the main justification for testing, a lack of consensus remains in the case of childhood-onset disorders for which preventive or therapeutic measures are not available. ispartof: Clinical Genetics vol:70 issue:5 pages:374-381 ispartof: location:Denmark status: published

In 2003, the UK Department of Health set out the genetics white paper, a plan for action and investment with particular emphasis on integration of genetic health care into primary care. Since the delivery of the genetics white paper, there has been little exploration of UK primary care doctors' attitudes towards extending their role to include provision of routine genetics services. We explored explore general practitioners' (GPs) attitudes towards provision of genetic health care including routine family history screening and familial risk assessment for common disorders in primary care using a quantitative, evaluative postal survey. Only 25% (797 of 3160) of the GPs returned a completed questionnaire. Although 32% of GPs supported collection of family history information and 41.5% familial risk assessment, 18% were not willing to offer these services even if training is provided. Of the GPs, 50% stated they recognized when referral to genetics services is appropriate, although 43% felt unprepared to collect family history or assess familial risk. Lack of training within the last 3 years was a significant predictor of feeling unprepared to undertake these activities (OR = 2.53,p = 0.012). A substantial group of GPs remain unprepared or unwilling to provide genetic health care. GPs' attitudes to delivery of genetic health care are significantly influenced by factors such as a lack of evidence of the direct benefits to patients, local guidelines and specialist services. These factors need addressing if delivery of genetic health care is to be incorporated into routine primary care.

A modification of Berry's test for the screening of mucopolysaccharides in urine, applicable with urine-impregnated filter paper, is presented. So far, 15,000 newborns have been screened with this method. Of these, 103 gave a positive test result at 20 days of age. At three months, 78 new samples were sent and of these, five continued to give a positive test. These five cam were followed-up for one year, and their study was completed by measuring thc activities of betagalactosidase, alfa-fucosidase and arylsulphatasc in urine. On the basis of the results, we re commend the systematic screening of large numbers of newborns in order to establish when abnormal urinary elimination of mucopolysaccharides begins in affected babies; this fact is of unquestionable practical importance for the clarification of the many unknown points that exist with respect to the genetical, biochemical and physiological aspects of this group of diseases.

In an optimalised radiochemical procedure for simultaneous measurement of hypoxanthine-guanine phosphoribosyl transferase (HG-PRT) and adenine phosphoribosyl transferase (A-PRT) from individual human hair roots, the HG-PRTIA-PRT activity ratio was used as an index for heterozygote detection in the Lesch-Nyhan syndrome. Hair roots of female carriers of HG-PRT deficiency could be distinguished from those of normal and mutant individuals. Evidence is presented that temperature at which hair roots are frozen prior to the enzyme assays affects the HG-PRTIA-PRT activity ratio The ratio tends to be higher after lower freezing temperatures.

Two hundred and ninety-seven blind Mexican individuals were screened for sulfur-containing amino acids in the urine, using cyanide-nitroprusside and silver-nitroprusside tests. Samples giving positive or doubtful results were further investigated by one-way paper chromatography. Five patients with homocystinuria were found; two of them had congenital cataract, one had optic disc atrophy, one had pigmentary retinosis and the remaining one had albinism. Excluding cases due to environmental factors, the prevalence of homocystinuria among blind people in Mexico City comes close to two per cent.

We present the results of a study of the porphyrin-forming enzymes in the erythrocytes of a recently detected case of CBP, in the immediate family, and in the family of a second cousin who died in infancy with a clinical picture similar lo that seen in the present patient. Except for a moderate increase in the activity of the uroporphyrinogen synthetase in the patient's lysates no patological changes have been found either in the patient or in any of the other persons studied. Our findings do not exclude the possibility that impaired activity of the isomerase (uroporphyrinogen-III-cosynthetase) plays a role, but they do indicate that this is not the only or even the most important metabolic error in the present type of erythropoictic porphyria. A study of the kinship between the two families seems to make a simple autosomal recessive in. heritance unlikely, hut does not exclude dominant inheritance by a rare single gene with low penetrance carried by the fathers. It is possible that the present case may represent a type of porphyria variegata in which the metabolic defect in porphyrin biosynthesis is located not in the liver hut in the bone marrow.

Aspartylglucosaminuria (AGU) is a genetic lysosomal storage disorder which probably affects the metabolism of glycoproteins. Earlier studies have shown a deficiency of a lysosomal hydrolase, N-aspartyl-β-glucosaminidase in the serum and seminal fluid, as well as in the brain and liver tissues of the patients. The present studies demonstrated a very low activity of N-aspartyl-β-glucosaminidase in cultured skin fibroblasts from AGU patients. The fibroblasts of the parents of the patients had a moderately low enzyme activity when conipared with control cultures. Thus, demonstration of the enzyme defect in fibroblasts offers possibilities both for detection of heterozygotes and for prenatal diagnosis of AGU.

We have prepared a new substrate from a keratan sulfate-derived-oligosaccharide (2-acetamido-2-deoxyglucosyl-(1--3)-[1-3H] Galactitol), which is necessary to measure beta-N-acetylhexosaminidase activity. This substrate was prepared from a cornea keratan sulfate by digestion with endo-beta-galactosidase, followed by isolation of disaccharide on gel filtration chromatography and chemical desulfation. Using this substrate, we found that a striking deficiency of beta-N-acetylhexosaminidase activity was present in the skin fibroblasts of patients with Sandhoff disease but not in Tay-Sachs disease. Both beta-N-acetyl-hexosaminidase A & H contributed to the catabolism of keratan sulfate.

Exome sequencing (ES) enhanced the diagnostic yield of genetic testing, but has also increased the possibility of uncertain findings. Prenatal ES is increasingly being offered after a fetal abnormality is detected through ultrasound. It is important to know how to handle uncertainty in this particularly stressful period. This systematic review aimed to provide a comprehensive overview of guidelines available for addressing uncertainty related to prenatal chromosomal microarray (CMA) and ES. Ten uncertainty types associated with prenatal ES and CMA were identified and defined by an international multidisciplinary team. Medline (all) and Embase were systematically searched. Laboratory scientists, clinical geneticists, psychologists, and a fetal medicine specialist screened the papers and performed the data extraction. Nineteen papers were included. Recommendations generally emphasized the importance of trio analysis, clinical information, data sharing, validation and re‐analysis, protocols, multidisciplinary teams, genetic counselling, whether to limit the possible scope of results, and when to report particular findings. This systematic review helps provide a vocabulary for uncertainties, and a compass to navigate uncertainties. Prenatal CMA and ES guidelines provide a strong starting point for determining how to handle uncertainty. Gaps in guidelines and recommendations were identified and discussed to provide direction for future research and policy making., Guidelines for prenatal chromosomal microarray (CMA) and Exome Sequencing (ES) were identified through a systematic review and summarized within a framework of ten defined uncertainty types associated with this prenatal genetic testing. This paper aimed to provide a vocabulary for prenatal genetic uncertainty, as well as a compass to navigate these uncertainties.

Dysferlinopathies are a clinically heterogeneous group of diseases caused by mutations in the DYSF gene encoding the dysferlin protein. Dysferlin is mostly expressed in muscle tissues and is localized in the sarcolemma, where it performs its main function of resealing and maintaining of the integrity of the cell membrane. At least four forms of dysferlinopathies have been described: Miyoshi myopathy, limb-girdle muscular dystrophy type 2B, distal myopathy with anterior tibial onset, and isolated hyperCKemia. Here we review the clinical features of different forms of dysferlinopathies and attempt to identify genotype-phenotype correlations. Because of the great clinical variability and rarety of the disease and mutations little is known, how different phenotypes develop as a result of different mutations. However, missense mutations seem to induce more severe disease than LoF, which is typical for many muscle dystrophies. The role of several specific mutations and possible gene modifiers is also discussed in the paper.

This paper reports on an investigation into the differences in image quality of different components used in a digital image processing system for chromosome analysis. As chromosome aberrations are important tools in the cloning of genes, it is important to know if the introduction of computerized analysis systems increases the risk of missing small aberrations. In this investigation the number of visible bands on a number of chromosomes has been used as a measure of quality. The images compared are microscope ocular images, photographs from a microscope built-in camera, digital images from a high and from a standard resolution camera, presented both on screen and print-out on paper. The main conclusions are that : (1) the view in the microscope ocular gives the best resolution, (2) there are risks of losing vital information using the digital image processing system for chromosome analysis, and (3) this risk is significantly reduced when using a high resolution camera.

The aim of this paper is to clarify some of the concepts used in the calculation of risk in genetic counselling. The use of probability as a measure of risk in a particular case is reviewed, with special reference to the Fisher - Neyman controversy. The technical concept of likelihood is then introduced and applied to risk probabilities themselves. The difficulties of interpretation are discussed, with a distinction drawn between calculating the risk for a child and inferring the genotype of his mother, even though the risk is wholly determined by the genotype. Fiducial inference is briefly mentioned, and the paper ends with a discussion of the problem which arises when the functional relationship between an unknown parameter and the unknown risk is not 1:1. The conclusion is tentatively reached that risk can only be gauged by probability and thus that prior probabilities must sometimes be assumed, but the paper is primarily intended as a guide and catalyst for the informed discussion of some of the difficulties, which may involve ethical dilemmas.

Familial male pseudohermaphroditism represents a group of clinically and genetically heterogeneous conditions. The “complete” or most severe forms of the Swyer syndrome and the “feminizing testes syndrome” (FTS) are easy to diagnose and to differentiate from the other types of genetic male pseudohermaphroditism. This paper deals primarily with one of these conditions: pseudovaginal perineoscrotal hypospadias (PPSH) which presumably is due to the homozygous state of an uncommon recessive gene and which is (classically) characterized by perineoscrotal hypospadias with either a separate perineal vaginal opening or a utricular “pseudovaginal” outpouching of the urethra, cleft scrotum-like labioscrotal folds, each containing a grossly and microscopically normal testis with epididymis and rudimentary vas deferens, absence of Mullerian duct derivatives, striking virilization at puberty, usually with no or only minimal gynecomastia. The authors report one sporadic and nine familial cases of PPSH from five families and discuss the differential diagnosis of PPSH primarily with respect to the so-called incomplete feminizing testes syndrome(s) (IFTS), the “Reifenstein syndrome”, and the “incomplete” forms of the Swyer syndrome. The pertinent available reports on PPSH, the IFTS, and the Reifenstein syndrome are abstracted in separate appendices to this paper.

A prototype database of published articles containing data on the frequency of human inherited disorders has been developed for use in clinical contexts, in medical research, for epidemiological studies, and in the planning of genetic services. It can be accessed at http://www.uwcm.ac.uk/uwcm/mg/fidd/. The information available in the literature comes from a wide range of publications, not all can be described primarily as epidemiological surveys. A preliminary assessment indicated that the quality of published articles was highly variable. Very few published articles describe quality-scoring systems for epidemiological surveys in general. We have developed a new scoring system to assess the quality of published articles on genetic disease frequency based on five main criteria and nine component scores. We carried out a first pilot study, to test its feasibility, usefulness and reproducibility. Eleven assessors scored six papers on the epidemiology of Huntington disease. As a result of these findings, we modified the scoring system to define each component more clearly. This was then evaluated in a second pilot study, which utilized six assessors to score 20 papers. The consensus between assessors remained relatively poor. We feel that while it may be possible to improve the scoring system further, the degree of improvement attainable may be limited by the poor standards of content and presentation of published surveys, which led to confusion and uncertainty by assessors. This pilot exercise has shown the need to raise the awareness of researchers and clinicians about the basic quality standards to be required of epidemiological genetic surveys.

The recently re-named pre-implantation genetic testing for determining embryo aneuploidies (PGT-A) is presently very popular although its acceptance by the scientific community is controversial. This approach still encounters drawbacks. This paper uses a SWOT (strengths, weaknesses, opportunities and threats) analysis to discuss salient points to be considered when examining the pre-implantation genetic testing (PGT-A) strategy to gather information from a range of perspectives. One of the strengths associated with the procedure is represented by an increase in implantation rate although data from the highest level of evidence do not support an increase in cumulative pregnancy rates. The current difficulty in the management of mosaicisms represents a weakness of PGT-A. The application of the strategy represents an opportunity to favor the single embryo transfer while other advantages, such as reduction of time to pregnancy and emotional distress are controversial. Potential important threats, at present still undefined, are represented by the biopsy-related damage to the blastocyst and the impact on neonatal and long-term outcomes.

For many years, a considerable number of patients with autoimmune diseases (ADs) have suffered from a lack of drug response and drug-related toxicity. Despite the emergence of new therapeutic options such as biological agents, patients continue to struggle with these problems. Unfortunately, new challenges, including the paradoxical effects of biological drugs, have complicated the situation. In recent decades, efforts have been made to predict drug response as well as drug-related side effects. Thanks to the many advances in genetics, evaluation of markers to predict drug response/toxicity before the initiation of treatment may be an avenue toward personalizing treatments. Implementing pharmacogenetics and pharmacogenomics in the clinic could improve clinical care; however, obstacles remain to effective personalized medicine for ADs. The present study attempted to clarify the concept of pharmacogenetics/pharmacogenomics for ADs. After an overview on the pathogenesis of the most common types of treatments, this paper focuses on pharmacogenetic studies related to the selected ADs. Bridging the gap between pharmacogenetics and personalized medicine is also discussed. Moreover, the advantages, disadvantages and recommendations related to making personalized medicine practical for ADs have been addressed.

This paper presents the largest study in Cyprus evaluating the frequency and distribution of BRCA1/2 mutations in a high risk patient cohort. Deleterious mutations in the BRCA1/2 genes were identified in 68 of the 527 patients tested (13%). It is of interest that a quarter of those tested positive, did not have an extensive family history of breast/ovarian cancer but were diagnosed with early onset breast cancer, ovarian cancer under the age of 60 or triple negative breast cancer. The spectrum of mutations identified in our patient cohort is different compared to other Mediterranean countries. Furthermore, several of the mutations detected are novel and have not been identified in other ethnic populations. This highlights the importance of operating a national reference center for cancer genetic diagnosis which offers services tailored to the needs of the Cypriot population.

This paper examines how COMT158 genotypes and plasma proline levels are associated with variable penetrance of social behavioural and social cognitive problems in 22q11.2 deletion syndrome (22q11DS). Severity of autistic spectrum symptoms of 45 participants with 22q11DS was assessed using the Autism Diagnostic Interview Revised. Face and facial emotion recognition was evaluated using standardized computer-based test-paradigms. Associations with COMT158 genotypes and proline levels were examined. High proline levels and poor face recognition in individuals with the COMTMET allele, and poor facial emotion recognition, explained almost 50% of the variance in severity of autism symptomatology in individuals with 22q11DS. High proline levels and a decreased capacity to break down dopamine as a result of the COMTMET variant are both relevant in the expression of the social phenotype in patients. This epistatic interaction effect between the COMT158 genotype and proline on the expression of social deficits in 22q11DS shows how factors other than the direct effects of the deletion itself can modulate the penetrance of associated cognitive and behavioural outcomes. These findings are not only relevant to our insight into 22q11DS, but also provide a model to better understand the phenomenon of variable penetrance in other pathogenic genetic variants.

Chromosomal aberration mostly occurs in chromosomes 21, 18 and 13, with an incidence approximately 1 out of 160 live births in humans, therefore making prenatal diagnosis necessary in clinics. Current methods have drawbacks such as time consuming, high cost, complicated operations and low sensitivity. In this paper, a novel method for rapid and accurate prenatal diagnosis of aneuploidy is proposed based on pyrosequencing, which quantitatively detects the peak height ratio (PHR) of different bases of segmental duplication. A direct polymerase chain reaction (PCR) approach was undertaken, where a small volume of amniotic fluid was used as the starting material without DNA extraction. Single-stranded DNA was prepared from PCR products and subsequently analyzed using pyrosequencing. The PHR between target and reference chromosome of 2.2 for euploid and 3:2 for a trisomy fetus were used as reference. The reference intervals and z scores were calculated for discrimination of aneuploidy. A total of 132 samples were collected, within trisomy 21 (n = 11), trisomy 18 (n = 3), trisomy 13 (n = 2), and unaffected controls (n = 116). A set of six segmental duplications were chosen for analysis. This method had consistent results with karyotyping analysis, a correct diagnosis with 100% sensitivity and 99.9% specificity.

We aimed to present a systematic review on Huntington's disease (HD) in Latin America (LA). PubMed and LILACS were searched up to March 2015, reporting confirmed HD cases in LA. Case series, cross-sectional, case-control, and prospective studies were included. From 534 communications, 47 were eligible. Population-based studies were not found; minimal prevalence of 0.5-4/100,000 was estimated for Venezuela and Mexico. Geographical isolates were well characterized in Venezuela and in Peru. CAG repeats at HTT gene varied between 7-33 and 37-112 in normal and expanded alleles, respectively. Intermediate alleles were found in 4-10% of controls. Ages at onset and the expanded CAG repeats correlated with r from - 0.55 to -0.91. While haplotype patterns of Venezuelan and Brazilian chromosomes were similar to those observed in Europeans, haplotypes from Peruvian HD patients did not match the same pattern. The limited number of papers found suggests that HD is poorly diagnosed in LA. Minimal prevalence seemed to be halfway between those of Caucasians and Asians. Range of CAG repeats was similar to those of Europeans. Haplotype studies indicate that majority of HD patients might be of Caucasian descent; an Asian origin for some Peruvian patients was proposed.

In-person genetic counselling (GC) is the model typically used to provide patients with information regarding their genetic testing options. Current and emerging demand for genetic testing may overburden the health care system and exceed the available numbers of genetic counsellors. Furthermore, GC is not always available at times and places convenient for patients. There is little evidence that the in-person model alone is always optimal and alternatives to in-person GC have been studied in genetics and other areas of health care. This review summarizes the published evidence between 1994 and March 2014 for interactive e-learning and decisional support e-tools that could be used in pre-test GC. A total of 21 papers from 15 heterogeneous studies of interactive e-learning tools, with or without decision aids, were reviewed. Study populations, designs, and outcomes varied widely but most used an e-tool as an adjunct to conventional GC. Knowledge acquisition and decisional comfort were achieved and the e-tools were generally well-accepted by users. In a time when health care budgets are constrained and availability of GC is limited, research is needed to determine the specific circumstances in which e-tools might replace or supplement some of the functions of genetic counsellors.

This paper describes a complex combination of four thalassemia genes (delta(+), beta(0), nondeletion and deletion alpha-thalassemia) in the spouse of a typical high Hb A2 beta-thalassemia carrier presenting for genetic counselling. This complex gene combination resulted in a hematological phenotype, characterized by thalassemia-like red cell indices, normal Hb A2 and Hb F levels and slightly reduced alpha/beta globin chain synthesis ratio, and therefore not indicative for the presence of beta-thalassemia trait. Family studies in combination with alpha-globin gene mapping, haplotype analysis at the beta-globin gene cluster and definition of the beta-thalassemia mutation by oligonucleotide hybridization led us to identify a beta-thalassemia mutation, to define the molecular basis for this phenotype and give the appropriate genetic counselling.

A high quality of cytogenetic preparations is important for maintaining a high standard in the cytogenetic laboratory. In the past, quality has been assessed by visual counting or estimation of the number of bands on chromosomes. In this paper we have counted bands automatically during karyotyping by using the Magiscan chromosome analysis system. A high correlation between automatic and visual counting was found, the automatic counting was reproducible and count figures were comparable when the karyotyping machines were operated by different technicians. The automatic counting procedure has now been included in our routine for 1 year. The highest numbers of bands were counted on slides from peripheral blood, with fewer bands for amniotic fluid and the lowest number for cells from chorionic villi. All three cell types showed significant variations in band number over time, which may be due to changes in weather conditions and/or the reagents used for cell culture, harvest and staining. It is concluded that the automatic counting procedure may be used to monitor the quality of metaphases over time and to set limits for band number on routine preparations acceptable for analysis.

A review of the literature about parents' experiences with amniocentesis is given in the first part of this paper. In the second part the results of a follow-up study in Belgium are presented. Three groups of women who had amniocentesis performed because of advanced maternal age, a previous child with Down syndrome or a previous child with neural tube defect, respectively, were interviewed at home about their experiences. Anxiety feelings were different between groups but also showed considerable variation within each group. The overall psychological evaluation of the procedure was positive, so that the majority of the women would opt for amniocentesis in a subsequent pregnancy and would recommend it to others. Later follow-up contact by mailed questionnaire revealed that almost all women elected for their subsequent pregnancies to be monitored by amniocentesis.

A presumed right not to know has been claimed in several discussions about testing for genetic diseases or genetic risks in families of populations. In this paper, ethical problems arising from the implementation of a possible right not to know are examined.

Medical genetics as a discipline has contributed basic knowledge of great applicability in environmental medicine, e.g. 1) the demonstration that environmental agents may cause chromosomal damage, 2) that chromosome aberrations are correlated with increased risks for cancer and spontaneous abortion, and 3) that the susceptibility to cyto- and genotoxic damage may be influenced by genetic factors. This paper discusses examples of applications of genetic knowledge in environmental medicine and areas for future research.

The osteopetroses are a heterogeneous group of disorders characterised by generalised bony sclerosis. The autosomal dominant form usually has a "benign" prognosis, in contrast to the "malignant" course of the autosomal recessive variety. In this paper we describe a kindred in which the phenotypic spectrum varied from an asymptomatic condition in adults to a severely affected infant, presenting with anaemia, hepatosplenomegaly, hydrocephalus and blindness. The findings in this family are reported and discussed to elucidate further the possible genetic heterogeneity in autosomal dominant osteopetrosis.

An emerging challenge facing those who are concerned about the efficacy of public health programs is to understand how information from the DNA revolution might be used to improve our ability to predict the initiation, progression and severity of a common disease having a complex multifactorial etiology. In the course of research to evaluate the role of information about DNA, combinations of genome types and environmental exposures that predispose to disease will be identified. Such information is expected to be useful in efforts to identify individuals and families at higher risk of disease and to predict their responses to a proposed therapy. This paper begins with a discussion of the features of a realistic biological model for the study of a common multifactorial disease. We present evidence for the complexity in the relationship between genome type variation and variation in risk of coronary artery disease (CAD) and review the preliminary results of our studies to determine whether information about genome type variation can improve our ability to predict the distribution of CAD among individuals in the population at large. Such studies make it apparent that new analytical strategies are necessary to deal with the plethora of genome type information available for the evaluation of risk of a common disease like CAD. This shift in the research paradigm will build upon new strategies to understand the organization of natural systems that are coming from outside the mainstream of genetic research.

This paper describes the first case of Hb Bart's hydrops fetalis syndrome in the Sardinian population. Despite the high frequency of a-thalassemia, fetal hydrops is extraordinarily rare in the Sardinian population because a-thalassemia is more usually the result of the single a-thalassemia globin gene deletion and is very rarely produced by the deletion of two a-globin genes. The fetus, the product of a consanguineous marriage at risk for beta-thalassemia, was monitored by chorionic villi DNA analysis which detected the heterozygous state for the codon 39 nonsense mutation. Follow-up ultrasound examination showed fetal hydrops, which led us to carry out further investigation. Hemoglobin and a-globin gene analysis on cord blood obtained by cordocentesis revealed the homozygous state for the most common deletion ao-thalassemia in Mediterranean populations. Retrospective evaluation of the father's hematological features showed very low MCH-MCV for a beta-thalassemia carrier which may indicate co-inherited a-thalassemia. These findings indicate that careful evaluation of red cell indices of parents at risk for beta-thalassemia and adequate consideration of the consanguinity may point to co-inherited a-thalassemia and lead to the appropriate analysis.

The present paper describes a girl with a small de novo deletion of chromosome 5(q33q34). Fluorescence in situ hybridisation with locus specific probes was used to define the extent of this deletion. Clinical features in this patient are microcephaly, dysmorphic facial features such as epicanthus, small biparietal distance and retrognathia, four-finger lines on both hands and mild mental retardation.

In Grampian region, the first 100 requests for predictive testing for Huntington's disease have been analysed. Forty-five presymptomatic predictive test results have been given, eleven families have made a decision to undergo prenatal exclusion tests, and so far eleven pregnancies have been investigated using chorion villus biopsy. This paper presents the protocol used and a descriptive analysis of those receiving results, those choosing to leave the programme, and those unable to complete it because of an unsuitable family structure or unco-operative relatives.

Fluorescent in situ hybridization with probes specific for a chromosomal subregion and chromosome-specific libraries (chromosome painting) are important new methods for assessing chromosome rearrangements. In this paper we present four patients with additional chromosomal material on chromosome 8p who have been studied using G-banding techniques, chromosome painting and FISH with cosmid probes specific for the region 8p23.1-->8pter. In all cases we found a partial inversion duplication of 8p along with a deletion of the region 8p23.1-->8pter.

We studied a mother and daughter with skeletal dysplasia which was characterized clinically by proximal and distal flexion contractures in the phalanges, and by brachydactyly, clinodactyly and ulnar and radial subdislocations of the fingers. Radiologically, the 2nd metacarpal in the daughter was seen to be longer than the other metacarpals, with bone carpal fusion, and flexion contractures of the fingers in both hands. Thoraco-lumbar xyphorotoscoliosis and malformed vertebrae with dyssegmentation of L2-L3, T12 and L1 with cuneiform shape, asymmetry of the pelvic bones and exostotic lesions in the proximal third of the tibia and the distal third of the femur were also noted. The clinical and radiological characteristics were compatible with the syndrome described by Christian et al. in 1975 and called the second metatarsal syndrome. The purpose of this paper was to present a second corroborative familial case and to propose another name: Christian's spondylo-digital syndrome.

In this paper we report a de novo 13/14 Robertsonian type translocation with apparent loss of band 14q11 in a mentally retarded, blind 24-year-old male. The findings in 10 other patients with a de novo Robertsonian D/D type translocation diagnosed in this center are reviewed.

In the present paper we report the first example of fertility in a female with isodicentric X-formation and karyotype 45,X/46,X,del(X)(pter----p21.3)/46,X,idic(X)(qter----p21.3::p21.3- ---qter). Her daughter was phenotypically almost normal and presented a 46,X,del(X)(pter----p21.3) karyotype in all examined cells.

In this paper we report detailed autopsy data of a malformed male newborn with 5p trisomy due to a de novo inverted 5p duplication, inv dup (5)(p13.1----p15.3), and we compare these data with the findings in previous reports on 5p trisomy. Cerebral malformations, i.e. agenesis of corpus callosum, and Dandy-Walker cyst malformations, seem to be another characteristic finding in this partial autosomal duplication syndrome.

This paper describes for the first time the clinical findings in a case of pure trisomy (1q)(q42----qter). Eight cases involving this trisomy have been reported previously, but these were complicated by additional chromosomal changes, and hence the assignation of a discrete phenotype remained doubtful. The clinical abnormalities reported here, most of which were included amongst others in the previous reports of trisomy (1q)(q42----qter), provide the basis for characterisation of this condition as a syndrome. These changes comprised macrocephaly, prominent forehead, micrognathia, large fontanelle, flat nasal bridge, low-set ears, facial capillary naevi, cardiac defect and small size for gestational age.

Phenylketonuria (PKU) is one of the most common inborn errors of metabolism with an annual incidence of approximately 1:16,000 live births in North America. Contemporary therapy relies upon lifelong dietary protein restriction and supplementation with phenylalanine-free medical foods. This therapy is expensive and unpalatable; dietary compliance is difficult to maintain throughout life. Non-adherence to the diet is associated with learning disabilities, adult-onset neurodegenerative disease, and maternal PKU syndrome. The fervent dream of many individuals with PKU is a more permanent cure for this disease. This paper will review ongoing efforts to develop viable cell-directed therapies, in particular cell transplantation and gene therapy, for the treatment of PKU.

In this paper we report a 22-year-old male with an asymmetric skeletal dysplasia, affecting almost the whole right part of the body and closely resembling pseudoachondroplastic dysplasia. This “segmental” type of chondrodysplasia is apparently another rare example of a somatic mutation of an autosomal dominant gene in man.

Congenital rigidity of multiple joints poses a difficult diagnostic and therapeutic problem. There are also semantic difficulties as the non-specific term “arthrogryposis” is often used for any individual with congenital limitation of joint movement. Many distinct syndromes present in this way and as they differ in their course, prognosis and genetic implications, diagnostic precision is crucial. A diagnostic analysis is given of 247 South African patients in whom “arthrogryposis” had been recorded, and the pathogenesis and nosology of congenital contractures are discussed in this paper. Three of these stiff joint conditions were originally described in South African patients, i.e. Liebenberg synostosis syndrome, digitotalar dysmorphism, and the Gordon syndrome of autosomal dominant cleft palate, camptodactyly and club feet.

A number of methods developed in different countries for the use of dermatoglyphics as an objective test for the confirmation of the clinical diagnosis of Down's syndrome were evaluated for a group of 308 Dutch individuals. Optimal results were obtained by the approach proposed at John Hopkins University (U.S.A.). The Hopkins composite score correctly scored 97.7 % of the individuals tested, whereas the Hopkins single pattern scoring method correctly scored 95.5 % of individuals. A simplified use of scoring methods is proposed in a forthcoming paper.

The dermatoglyphic discriminants proposed by Penrose & Loesch were used for differentiation between samples of 183 patients with Down's syndrome and 125 controls. The discriminant weightings determined for our Dutch individuals did not deviate much from those determined by Penrose & Loesch for individuals in Great Britain. The estimated percentage of misclassification compares well with the same quantity calculated in the original papers. Moreover, since the method compares well with other known scoring methods, it can be used to advantage in cases of unknown or discrepant symptoms in a patient. The disadvantage of the method, for the confirmation of a clinical diagnosis of Down's syndrome, seems to be that it is rather laborious.

This paper describes the unexpected transmission of a translocation (22;22)(p13;q11) from a mother to her phenotypically normal daughter (the proband). Both women had had multiple abortions. No signs of mosaicism with respect to chromosome No. 22 were found in the proband or in her mother. Until now, it has been generally assumed that carriers of a 22/22 translocation will have only abnormal conceptuses. The transmission of this translocation from a balanced carrier to a phenotypically normal daughter was therefore highly unexpected and is not easy to explain. Early postzygotic loss of a chromosome no. 22 from a trisomic zygote, or fertilization of an oocyte carrying the translocation by a sperm nullisomic for chromosome no. 22 could have led to the balanced chromosome pattern of the proband.

Thirty, presumably healthy, middle-aged males from Northern Sweden were studied in September 1973 and again in February 1975. Mean fasting cholesterol and triglyceride concentrations were significantly higher at the latter investigation than they were at the former in the total group and in the Lp(a+) group, but not among those who were Lp(a-). Furthermore, estimation of free thyroxine factor yielded significantly higher results in the Lp(a-) than in the Lp(a+) group. In a previous paper, we reported significant differences between Lp(a+) and Lp(a-) individuals with respect to the relationships between insulin level and blood glucose concentration, and between insulin level and fasting triglyceride concentration. The combined results of the present and previous studies suggest that inherited metabolic differences exist between Lp(a+) and Lp(a-) individuals. In view of the association which has been found between the phenotype Lp(a+) and coronary heart disease it seems plausible that these differences may be of clinical importance.

Apolipoprotein(a) [apo(a)] is a plasma glycoprotein that is highly polymorphic in size due to differences in the number of a tandemly arrayed cysteine-rich repeat called kringle (K)4 at its N-terminus. Most plasma apo(a) is covalently attached to apolipoprotein B-100 and circulates as part of lipoprotein(a) [Lp(a)]. A fraction of apo(a) circulates free of lipoproteins. Almost all of the free apo(a) consists of fragments containing variable numbers of K4 repeats derived from the N-terminal region. Previously we provided evidence suggesting that the apo(a) fragments present in human plasma are the source of the apo(a) fragments in human urine. If this were the case, it would be expected that plasma levels of fragments would be higher in subjects with end-stage renal disease (ESRD). In this paper we quantified the levels of apo(a) fragments and plasma Lp(a) in 26 Caucasian and 26 African-American subjects with ESRD and 52 healthy subjects matched for race, sex and the size of the apo(a) isoforms. The plasma levels of apo(a) fragments and Lp(a) were both higher in the ESRD subjects. In addition, the ratio of apo(a) fragments to total immunodetectable apo(a) was increased in ESRD. To determine how much the increase in the apo(a) fragments contributed to the increase in plasma Lp(a) in ESRD, the plasma Lp(a) levels were measured employing two different anti-apo(a) enzyme-linked immunoabsorption assays (ELISA). One assay detected both free and bound apo(a), whereas the other assay detected only bound apo(a). Although the plasma levels of apo(a) in the ESRD subjects tended to be higher using the assay that detected both fragments and full-length apo(a), the increase was modest. Thus, although a greater proportion of the apo(a) in ESRD plasma circulates as fragments, most of the elevation in plasma levels of Lp(a) associated with renal insufficiency is due to an increase in intact Lp(a).

Various degrees of bone marrow aplasia have been described in association with distinctive congenital anomalies such as the Fanconi Pancytopenia Syndrome (F.P.S.), Thrombocytopenia Absent Radii Syndrome (T.A.R. Syndrome) the Aase Syndrome and Diamond-Blackfan Anemia. This case report describes a child with pancytopenia and several dysmorphic features which have never collectively been described in any of the bone marrow aplasia syndromes listed above. In this paper, we report a constellation of dysmorphic features and pancytopenia which may constitute a new syndrome.

This paper suggests that there is probably a dominant, sex-linked type of chondrodysplasia punctata. Clinical data are reported for three girls with such a disorder. Two of their mothers showed a mild form of cicatricial alopecia. The pathognomonic dermatological findings in the children include erythematous skin changes and striated ichthyosiform hyperkeratosis during the first months of life. Later on, patterned ichthyosis, follicular atrophoderma, coarse, lusterless hair and cicatricial alopecia become evident. It is assumed that about one fourth of all cases with chondrodysplasia punctata reported in the literature belong to the dominant sex-linked type.

In this paper, we provide an overview of databases that are of importance to clinical geneticists. Some suggestions for the fruitful use for both research and diagnosis are given. For beginning 'web-surfers' we also list some well-known search engines and give a short overview of how to use these and other services. In addition, the URLs of some of the most important databases, gateways and tutorials are listed.

This paper describes a retarded girl who had a severe seizure disorder and a few minor anomalies, and who was found to have a "G-sized" supernumerary chromosome in all her cells which were examined. Studies of the patient's and her parents' chromosomes by a variety of techniques suggest that the supernumerary chromosome arose following a prezygotic maternal 13;15 translocation.

In this paper we report two clinically recognizable chromosomal syndromes, both resulting from isochromosome 18 formation, i.e. trisomy 18q and tetrasomy 18p. The possible mechanisms of the isochromosome formation are discussed and the literature on subject is reviewed.