Molecular and clinical study of 183 patients with conotruncal anomaly face syndrome

To investigate molecular and clinical aspects of conotruncal anomaly face (CAF), we studied the correlation between deletion size and phenotype and the mode of inheritance in 183 conotruncal anomaly face syndrome (CAFS) patients. Hemizygosity for a region of 22q11.2 was found in 180 (98%) of the patients with CAFS by fluorescence in situ hybridization (FISH) using the N25(D22S75) DiGeorge critical region (DGCR) probe. No hemizygosity was found in three (2%) of the patients with CAFS by FISH using nine DiGeorge critical region probes and a SD10P1 probe (DGA II locus). None of these three patients had mental retardation and just one had nasal intonation, which was observed in almost all of the 180 CAFS patients who carried deletions (mental retardation, 92%; nasal voice, 88%). Nineteen of 143 families (13%) had familial CAFS and 16 affected parents (84%) were mothers. Although only two of the affected parents had cardiovascular anomalies, the deletion size in the 16 affected parents and their affected family members, who were studied by FISH analysis, was the same. It indicates that extragenic factors may play a role in the genesis of phenotypic variability, especially in patients with cardiovascular anomalies. No familial cases were found among CAFS patients with absent thymus/DiGeorge anomaly (DGA). Also, in all 18 CAFS patients with completely absent thymus/DGA and all 6 CAFS patients with schizophrenia, it was revealed that the deletion was longer distally. A study of the origin of the deletion using microsatellite analyses in 48 de novo patients showed that in 65% of CAFS patients it was maternal, while in 64% of DGA patients it was paternal. The findings of this study indicated that CAF was almost always associated with the deletion of 22q11.2. As well as the major features of the syndrome, other notable extracardiac anomalies were found to be susceptibility to infection, schizophrenia, atrophy or dysmorphism of the brain, thrombocytopenia, short stature, facial palsy, anal atresia, and mild limb abnormalities. Received: 5 January 1998 / Accepted: 7 March 1998     

Whole dystrophin gene analysis by next-generation sequencing: a comprehensive genetic diagnosis of Duchenne and Becker muscular dystrophy

Duchenne/Becker muscular dystrophies are the most frequent inherited neuromuscular diseases caused by mutations of the dystrophin gene. However, approximately 30 % of patients with the disease do not receive a molecular diagnosis because of the complex mutational spectrum and the large size of the gene. The introduction and use of next-generation sequencing have advanced clinical genetic research and might be a suitable method for the detection of various types of mutations in the dystrophin gene. To identify the mutational spectrum using a single platform, whole dystrophin gene sequencing was performed using next-generation sequencing. The entire dystrophin gene, including all exons, introns and promoter regions, was target enriched using a DMD whole gene enrichment kit. The enrichment libraries were sequenced on an Illumina HiSeq 2000 sequencer using paired read 100 bp sequencing. We studied 26 patients: 21 had known large deletion/duplications and 5 did not have detectable large deletion/duplications by multiplex ligation-dependent probe amplification technology (MLPA). We applied whole dystrophin gene analysis by next-generation sequencing to the five patients who did not have detectable large deletion/duplications and to five randomly chosen patients from the 21 who did have large deletion/duplications. The sequencing data covered almost 100 % of the exonic region of the dystrophin gene by ≥10 reads with a mean read depth of 147. Five small mutations were identified in the first five patients, of which four variants were unreported in the dmd.nl database. The deleted or duplicated exons and the breakpoints in the five large deletion/duplication patients were precisely identified. Whole dystrophin gene sequencing by next-generation sequencing may be a useful tool for the genetic diagnosis of Duchenne and Becker muscular dystrophies.     

New haplotypes in the Bedlington terrier indicate complexity in copper toxicosis

Copper toxicosis (CT) is an autosomal recessive disorder common in Bedlington terriers. Previously, the CT locus was mapped to canine Chromosome (Chr) 10q26 through linkage to marker C04107. Diagnosis, traditionally based on liver biopsy, has recently shifted to interpretation of the C04107 microsatellite alleles where allele 2 segregates with the disease with 90–95% accuracy. Recently, CT has been attributed to a deletion of exon 2 in the MURR1 gene. We also identified a deletion of exon 2 of MURR1 in our collection of 2-2 homozygous affected terriers. However, our collection also included affected 1-1 homozygotes and 1-2 heterozygotes, and these dogs did not have the homozygous deletion. In addition to C04107, we analyzed an adjacent microsatellite (C04107B), and two novel SNPs, all within intron 1 of MURR1, and sequenced all exons and their intronic boundaries. Pedigree analysis indicates that there are two typical haplotypes, one normal and one affected, maintaining complete linkage disequilibrium between C04107 allele 2 and the deletion in most pedigrees. Most importantly, we identified a recombinant haplotype present in a North American pedigree, where allele 2 is not linked with the deletion, and a fourth haplotype containing a splice site variant. Although the splice site alteration appears to be a normal variant, it is present in two affected dogs, which do not carry homozygous deletions of MURR1.     

Familial mental retardation syndrome ATR-16 due to an inherited cryptic subtelomeric translocation, t(3;16)(q29;p13.3)

In the search for genetic causes of mental retardation, we have studied a five-generation family that includes 10 individuals in generations IV and V who are affected with mild-to-moderate mental retardation and mild, nonspecific dysmorphic features. The disease is inherited in a seemingly autosomal dominant fashion with reduced penetrance. The pedigree is unusual because of (1) its size and (2) the fact that individuals with the disease appear only in the last two generations, which is suggestive of anticipation. Standard clinical and laboratory screening protocols and extended cytogenetic analysis, including the use of high-resolution karyotyping and multiplex FISH (M-FISH), could not reveal the cause of the mental retardation. Therefore, a whole-genome scan was performed, by linkage analysis, with microsatellite markers. The phenotype was linked to chromosome 16p13.3, and, unexpectedly, a deletion of a part of 16pter was demonstrated in patients, similar to the deletion observed in patients with ATR-16 syndrome. Subsequent FISH analysis demonstrated that patients inherited a duplication of terminal 3q in addition to the deletion of 16p. FISH analysis of obligate carriers revealed that a balanced translocation between the terminal parts of 16p and 3q segregated in this family. This case reinforces the role of cryptic (cytogenetically invisible) subtelomeric translocations in mental retardation, which is estimated by others to be implicated in 5%-10% of cases.     

Lymphangiography: Its Practical Value in Surgically Staged Patients with Hodgkin's Disease

Since the introduction of “staging laparotomy” (to determine the disease''s stage) in assessing Hodgkin''s disease, some observers have argued that lymphangiography could be safely omitted in the initial diagnostic evaluation.To test these opinions a series of 75 patients with Hodgkin''s disease who had a staging laparotomy and histological correlation with lymphangiograms was reviewed. Of 16 examinations with positive results, one proved to be a false positive. Of the 14 examinations with equivocal results, one proved histologically positive. In the remaining 45 lymphangiograms, five were falsely negative. In all five of these patients abdominal lymph nodes were involved, but in areas that do not routinely opacify on lower extremity lymphangiography. The overall accuracy was 90 percent.Therapeutically, the lymphangiogram permits accurate planning for treatment by radiation therapy so that all known disease is treated and yet bone marrow is not excessively irradiated. Changes in lymph node architecture after therapy provide valuable information as to regression of the disease or signs of its early recurrence.     

Same-Day Diagnosis Based on Histology for Women Suspected of Breast Cancer: High Diagnostic Accuracy and Favorable Impact on the Patient

Background

Same-day diagnosis based on histology is increasingly being offered to patients suspected of breast cancer. We evaluated to which extent same-day diagnosis affected diagnostic accuracy and patients'' anxiety levels during the diagnostic phase.

Patients and methods

All 759 women referred for same-day evaluation of suspicious breast lesions between November 2011–March 2013 were included. Diagnostic accuracy was assessed by linking all patients to the national pathology database to identify diagnostic discrepancies, in which case slides were reviewed. Patients'' anxiety was measured in 127 patients by the State Trait and Anxiety Inventory on six moments during the diagnostic workup and changes over time (< = 1 week) were analyzed by mixed effect models.

Results

Core-needle biopsy was indicated in 374/759 patients (49.3%) and in 205/759 (27%) patients, invasive or in situ cancer was found. Final diagnosis on the same day was provided for 606/759 (79.8%) patients. Overall, 3/759 (0.4%) discordant findings were identified. Anxiety levels decreased significantly over time from 45.2 to 30.0 (P = <0.001). Anxiety levels decreased from 44.4 to 25.9 (P = <0.001) for patients with benign disease, and remained unchanged for patients diagnosed with malignancies (48.6 to 46.7, P = 0.933). Time trends in anxiety were not affected by other patient or disease characteristics like age, education level or (family) history of breast cancer.

Conclusion

Same-day histological diagnosis is feasible in the vast majority of patients, without impairing diagnostic accuracy. Patients'' anxiety rapidly decreased in patients with a benign diagnosis and remained constant in patients with malignancy.     

Unexplained left ventricular hypertrophy: consider a diagnosis of Fabry's disease

Lysosomal storage disorders are a group of disorders characterised by the deficiency of a specific lysosomal hydrolase. These diseases are rare, with only a few hundred patients in the Netherlands. Fabry''s disease, an X-linked lysosomal storage disorder, is caused by a deficiency of the lysosomal enzyme α-galactosidase A which results in, among other things, left ventricular hypertrophy, renal failure and cerebrovascular events. Patients with Fabry''s disease, especially males, have a decreased life expectancy. Recent studies have shown that Fabry''s disease may be much more common among patients with left ventricular hypertrophy (LVH) than previously thought. Up to 7% of male patients with left ventricular hypertrophy and up to 12% of female patients with unexplained LVH were found to suffer from Fabry''s disease. Thus, Fabry''s disease should be considered in patients with unexplained LVH. This case report summarises the main features of the disease. In addition recent developments concerning prevalence, diagnosis and the current available treatments are discussed and an algorithm on who and how to screen for Fabry''s disease is presented.     

Decreased tuftsin concentrations in patients who have undergone splenectomy.

Serum tuftsin concentrations were measured, using a radioimmunoassay developed in Israel, in normal subjects and in patients who had undergone splenectomy. Concentrations in those who had undergone traumatic and elective splenectomy were much lower. The tuftsin concentration in 38 patients with Hodgkin''s disease who had undergone splenectomy during staging laparotomy was not significantly different from the mean concentration in other patients who had had elective splenectomy. In four patients who underwent splenectomy for non-malignant haematological disorders measurements made before and after operation showed that tuftsin concentrations fell significantly in the days after operation. The increased susceptibility to overwhelming infections of patients with Hodgkin''s disease and others who have undergone splenectomy may be related to the low tuftsin concentrations. As pre-splenectomy tuftsin concentrations in patients with Hodgkin''s disease were normal, the practice of performing staging laparotomy and splenectomy in patients with Hodgkin''s disease should perhaps be reconsidered.     

Commentary: assessing the effects of environmental pollution when people know that they have been exposed.

OBJECTIVE: To examine the effectiveness of routine clinic review in detecting relapse after treatment for Hodgkin''s disease. DESIGN: Review of hospital records. SETTING: Regional centre for cancer treatment and research. SUBJECTS: 210 patients with Hodgkin''s disease recruited to a chemotherapy trial protocol between 1984 and the end of 1990 who had achieved a complete or partial remission after treatment. MAIN OUTCOME MEASURES: The number of clinic visits made by patients over the period of observation, the number of relapses occurring during that time, and the route by which relapse was detected. RESULTS: The 210 patients generated 2512 outpatient reviews, and 37 relapses were detected. Thirty relapses (81%) were diagnosed in patients who described symptoms, which in 15 cases had resulted in an earlier appointment being arranged. In only four cases (11%; 95% confidence interval 4% to 25%) was relapse detected as a result of routine physical examination on investigation of a patient who did not have symptoms. CONCLUSIONS: Relapse of Hodgkin''s disease after treatment is usually detected as a result of the investigation of symptoms rather than by routine screening of asymptomatic patients. It is therefore proposed that the frequency of routine follow up visits should be reduced and greater emphasis placed on patient education. This should underline the importance of symptoms and encourage patients to arrange an earlier appointment if these develop.     

Epimutations in Prader-Willi and Angelman syndromes: a molecular study of 136 patients with an imprinting defect

Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are neurogenetic disorders that are caused by the loss of function of imprinted genes in 15q11-q13. In a small group of patients, the disease is due to aberrant imprinting and gene silencing. Here, we describe the molecular analysis of 51 patients with PWS and 85 patients with AS who have such a defect. Seven patients with PWS (14%) and eight patients with AS (9%) were found to have an imprinting center (IC) deletion. Sequence analysis of 32 patients with PWS and no IC deletion and 66 patients with AS and no IC deletion did not reveal any point mutation in the critical IC elements. The presence of a faint methylated band in 27% of patients with AS and no IC deletion suggests that these patients are mosaic for an imprinting defect that occurred after fertilization. In patients with AS, the imprinting defect occurred on the chromosome that was inherited from either the maternal grandfather or grandmother; however, in all informative patients with PWS and no IC deletion, the imprinting defect occurred on the chromosome inherited from the paternal grandmother. These data suggest that this imprinting defect results from a failure to erase the maternal imprint during spermatogenesis.     

Effect of genetic counselling on the prevalence of Huntington's chorea.

The relative fertility of sons and daughters of patients with Huntington''s chorea was found to be a little under 0.5 if they had been told of their risk of transmitting the disease before they had started their families. The effect was much the same in those who had attended the genetic clinic at The Hospital for Sick Children on a single occasion and those who had been told of their risk directly, or indirectly through the patient''s spouse or family doctor, by the neurologist who was looking after their affected parent at the National Hospital for Nervous Diseases. If all offspring of patients were informed of their risk the effect on the prevalence of the disorder would be substantial, especially if the mutation rate is low and the reproductive fitness of patients in the past has been close to 1.0. Men and women at risk of developing the disease should not be seen on just one occasion, however: they need continued support by being seen regularly at a special neurological genetic clinic.     

Strong correlation of elastin deletions,detected by FISH,with Williams syndrome: evaluation of 235 patients.

Williams syndrome (WS) is generally characterized by mental deficiency, gregarious personality, dysmorphic facies, supravalvular aortic stenosis, and idiopathic infantile hypercalcemia. Patients with WS show allelic loss of elastin (ELN), exhibiting a submicroscopic deletion, at 7q11.23, detectable by FISH. Hemizygosity is likely the cause of vascular abnormalities in WS patients. A series of 235 patients was studied, and molecular cytogenetic deletions were seen in 96% of patients with classic WS. Patients included 195 solicited through the Williams Syndrome Association (WSA), plus 40 clinical cytogenetics cases referred by primary-care physicians. Photographs and medical records of most WSA subjects were reviewed, and patients were identified as "classic" (n = 114) or "uncertain" (n = 39). An additional 42 WSA patients were evaluated without clinical information. FISH was performed with biotinylated ELN cosmids on metaphase cells from immortalized lymphoblastoid lines from WSA patients and after high-resolution banding analysis on clinical referral patients. An alpha-satellite probe for chromosome 7 was included in hybridizations, as an internal control. Ninety-six percent of the patients with classic WS showed a deletion in one ELN allele; four of these did not show a deletion. Of the uncertain WS patients, only 3 of 39 showed a deletion. Of the 42 who were not classified phenotypically, because of lack of clinical information, 25 patients (60%) showed a deletion. Thirty-eight percent (15/40) of clinical cytogenetics cases showed an ELN deletion and no cytogenetic deletion by banded analysis. These results support the usefulness of FISH for the detection of elastin deletions as an initial diagnostic assay for WS.     

Molecular genetic evidence for a founder effect in familial hypercholesterolemia among French Canadians

Summary Familial hypercholesterolemia (FH), at a prevalence of about 1 in 200 in the French-Canadian population, is caused by a 10-kb deletion in the low-density lipoprotein (LDL) receptor gene in 60% of French-Canadian FH heterozygotes. We genotyped 159 FH patients who carry this common mutation and 221 healthy French-Canadian controls for five DNA restriction fragment length polymorphisms (RFLPs) of the LDL receptor gene. The allele numbers for four of the five RFLPs differed significantly (P < 0.001) between FH patients and control subjects. Our results suggest that the 10-kb deletion carrier allele is associated with a single haplotype (called the B haplotype). In a family study including a patient homozygous for the 10-kb deletion, we showed that the B haplotype cosegregates with the deletion in affected members and that the B haplotype is also associated with the normal allele in some members of the family. We identified 15 different haplotypes for the normal allele in 10-kb deletion carrier FH heterozygotes. These results offer strong support, at a molecular level, for the hypothesis of a founder effect for the 10-kb deletion in the French-Canadian population.This work was presented in part at the meeting: Advances in Gene Technology: the molecular biology of human genetic disease, Miami, Florida, 1991     

Mitochondrial DNA deletion Δ4977 in peptic ulcer disease

Reactive oxygen species (ROS) play a critical role in peptic ulcer disease (PUD). Due to the high rate of ROS production and limited capacity for DNA repair within mitochondria, mtDNA is susceptible to oxidative damage and mutations. mtDNA deletion Δ4977 is one of the most common deletion events identified in mitochondria. We examined the association of 4977-bp mtDNA deletion with PUD. Genotypes were determined in bioptic samples of 150 PUD patients and 190 controls. The 4977-bp mtDNA deletion was found more frequently among patients with PUD (52%) than among controls (22.63%). The strong association between the mtDNA 4977-bp deletion and PUD was confirmed (OR = 3.7; 95% CI, 2.32–5.91; P = 0.0001). The 4977-bp deletion in mitochondrial DNA may be a risk factor for PUD, or may reflect an increase in oxidative stress that commonly accompanies underlying PUD disease. Larger population-based studies are needed to uncover the possible causal relationship between this deletion and peptic ulcer disease.     

Primary hypogammaglobulinaemia and arthritis.

Arthritis may be the first clinical manifestation of primary hypogammaglobulinaemia. In 16 years of 281 patients who had immunodeficiency, 30 had arthritis at presentation. It was more common in Bruton''s disease (15 (22%) of 69 patients) than in other forms of immunodeficiency (15 (7%) of 212 patients). Non-septic arthritis was more prevalent than septic arthritis, particularly monoarticular arthritis in Bruton''s disease and pauciarticular disease in common variable immunodeficiency. Boys in whom a diagnosis of Bruton''s disease was delayed were likely to develop recurrent infections complicated by arthritis. The measurement of serum immunoglobulin concentrations readily differentiates immunodeficiency from conditions such as Still''s disease and dictates subsequent management.     

Reliability of reported family history of myocardial infarction.

OBJECTIVE--To assess the reliability of reported family histories of myocardial infarction. DESIGN--A case-control study in which reported histories of first degree relatives were validated from death certificates, general practitioners'' records, and hospital notes. SETTING--Participants enrolled in the Belfast centre of the World Health Organisation''s study monitoring trends and determinants in cardiovascular disease (MONICA). SUBJECTS--200 men who survived myocardial infarction and 200 age matched controls drawn randomly from the population. MAIN OUTCOME MEASURES--The sensitivity, specificity, positive predictive value, and proportion of overall agreement with validated records of reported family histories of myocardial infarction in first degree relatives; odds ratios for myocardial infarction, given at least one reported relative or at least one verified relative being affected. RESULTS--349 of the 400 probands provided detailed family histories, reporting on 2812 first degree relatives. The overall sensitivity, specificity, and positive predictive value of reported histories were 67.3%, 96.5%, and 70.5% for cases and 68.5%, 97.7%, and 73.8% for controls. The kappa coefficients were modest: 0.65 for cases and 0.68 for controls. The odds ratios for myocardial infarction, given at least one affected relative, were not substantially inflated by recall bias. Some recall bias was evident for the probands'' reports of their siblings'' histories of myocardial infarction, the odds ratio for a reported history being 1.67 (95% confidence interval 1.09 to 2.57) and for the validated history 1.54 (1.01 to 2.37). CONCLUSIONS--Although the relative risk of disease is correctly estimated, the predictive accuracy of a casual family history of myocardial infarction may limit the effectiveness of targeted screening programmes. They may, however, complement other strategies based on genetic testing.     

Prevalence of symptoms of Raynaud's phenomenon in general practice.

OBJECTIVE--To investigate the prevalence of Raynaud''s phenomenon in the populations of five general practices. DESIGN--Two populations studied. A questionnaire was given to all new patients attending five general practices over four weeks, and the same questionnaire was sent by post to a random sample of adults from two of the practices. SETTING--General practices in inner London, Merseyside, and Cheshire. SUBJECTS--1532 Patients who completed questionnaires (1119 who attended the surgeries (response rate unknown) and 413 respondents to the postal survey (response rate 69%)). MAIN OUTCOME MEASURES--Response to questionnaire on symptoms of Raynaud''s phenomenon: patients were regarded as having the disease if they had episodes of blanching of the fingers that were precipitated by cold and accompanied by sensory symptoms (pins and needles or numbness). Subsequent interview and clinical appraisal of patients with the disease according to their responses to the questionnaire. RESULTS--The prevalence of Raynaud''s phenomenon was 11% (26/231) and 19% (34/182) respectively in men and women who completed the postal questionnaire and 16% (56/357) and 21% (157/762) respectively in those who completed the questionnaire when attending their general practice. Thus the overall rates were slightly higher in women, but there was no effect of age even after adjustment of the rates for practice and method of survey. CONCLUSION--The prevalence of Raynaud''s phenomenon is high compared with the low number of patients who seek treatment for the disease.