Phenotypic heterogeneity in 22q11.2 deletion syndrome: Copy Number Variants as genetic modifiers for congenital heart disease in a Brazilian cohort.

The clinical heterogeneity in 22q11.2 deletion syndrome (22q11.2DS) underlies complex genetic mechanisms including variants in other regions of the genome, known as genetic modifiers. Congenital heart disease (CHD) is one of the most relevant phenotypes in the syndrome and copy number variants (CNVs) outside the 22q11.2 region could play a role in its variable expressivity. Since those described loci account for a small proportion of the variability, the CNV analysis in new cohorts from different ancestry-based populations constitutes a valuable resource to identify a wider range of modifiers. We performed SNP-array in 117 Brazilian patients with 22q11.2DS, with and without CHD, and leveraged genome-wide CNV analysis. After quality control, we selected 50 CNVs in 38 patients for downstream analysis. CNVs' genetic content and implicated biological pathways were compared between patients with and without CHD. CNV-affected genes in patients with CHD were enriched for several functional terms related to ubiquitination, transcription factor binding sites and miRNA targets, highlighting the complexity of the phenotype's expressivity. Cardiac-related genes were identified in both groups of patients suggesting that increasing risk and protective mechanisms could be involved. These genes and enriched pathways could indicate new modifiers to the cardiac phenotype in 22q11.2DS patients.

Chronic exertional compartment syndrome in the differential diagnosis of peripheral artery disease in older patients with exercise-induced lower limb pain.

OBJECTIVE: Peripheral artery disease (PAD) and chronic exertional compartment syndrome (CECS) both cause exercise-induced lower limb pain. CECS is mostly described in young individuals and may therefore not be considered in older patients with intermittent claudication. The aim of our study was to identify differences in characteristics and symptomatology between patients with CECS and PAD that may help in recognizing CECS in patients ≥50 years with exercise-induced lower limb pain. METHODS: In this case-control study, patients with CECS ≥50 years were selected from a prospectively followed cohort and compared with a sample of newly diagnosed patients with PAD ≥50 years. A questionnaire assessed frequency and severity of lower limb pain, tightness, cramps, muscle weakness, and altered skin sensation at rest and during exercise. RESULTS: At rest, patients with CECS (n = 43, 42% female, 57 years; range, 50-76 years) reported significantly more pain, tightness, muscle weakness and altered skin sensation (all P < .01) than patients with PAD (n = 41, 39% female, 72 years; range, 51-93 years). Having CECS was associated with a significantly higher combined symptom score at rest (P = .02). During exercise, patients with CECS experienced more tightness, muscle weakness and altered sensation (P < .01), but not pain and cramps (P = .36; P = .70). Exercise-induced complaints occurred much later in patients with CECS than in patients with PAD (15 minutes vs 4 minutes; P < .01). Persistence of pain over 4.5 minutes proved most discriminative for the presence of CECS (sensitivity, 95%; specificity, 54%; positive predictive value, 65%). Exercise cessation completely alleviated complaints in all patients with PAD (n = 41) but not in 73% (n = 29) of the patients with CECS. Ongoing discomfort strongly predicted the presence of CECS (sensitivity, 73%; specificity, 100%; positive predictive value, 100%). CONCLUSIONS: Patients with CECS ≥50 years report a symptom pattern that is different from patients with PAD. These differences may aid vascular surgeons in identifying older patients with CECS.

Suboptimal Adherence in Clinical Practice to Guidelines Recommendation to Screen for Lynch Syndrome.

BACKGROUND: Identification of Lynch syndrome (LS) followed by annual/biannual surveillance colonoscopy markedly reduces the risk of developing new colorectal cancer (CRC) among those with LS. AIMS: (1) To determine the current practice of identifying LS in the USA and Canada, and current surveillance and management practices for those diagnosed with LS; (2) to determine whether variances in current practice are physician/region dependent or influenced by ease of access to specialist clinics. METHODS: An online survey request was sent to practicing gastroenterologists through the Canadian Association of Gastroenterology and the American College of Gastroenterology. Fisher's exact tests were performed to determine the factors associated with screening for LS and separately for follow-up, surveillance, and management. RESULTS: A total of 249 participants were recruited, of which 237 were gastroenterologists and included in the analysis. Less than one-third of practicing gastroenterologists indicated that their CRC patients were undergoing screening tests to identify LS. While 42% (65/153) of participants from the USA stated that their patients were undergoing universal LS screening (i.e., among all diagnosed with CRC), only 12% (6/49) of participants from Canada reported this practice (p < 0.001). There was no difference in reported practice between the physicians that do and do not have access to hereditary clinics (35% vs. 34% testing; p = 0.54). Appropriate surveillance interval to look for CRC in patients with LS was recommended by most. CONCLUSION: This survey suggests there is a significant difference in practice between Canada and the USA in regard to identification of LS, with suboptimal practice throughout North America.

Richieri-Costa-Pereira syndrome: Expanding its phenotypic and genotypic spectrum.

Richieri-Costa-Pereira syndrome is a rare autosomal recessive acrofacial dysostosis that has been mainly described in Brazilian individuals. The cardinal features include Robin sequence, cleft mandible, laryngeal anomalies and limb defects. A biallelic expansion of a complex repeated motif in the 5' untranslated region of EIF4A3 has been shown to cause this syndrome, commonly with 15 or 16 repeats. The only patient with mild clinical findings harbored a 14-repeat expansion in 1 allele and a point mutation in the other allele. This proband is described here in more details, as well as is his affected sister, and 5 new individuals with Richieri-Costa-Pereira syndrome, including a patient from England, of African ancestry. This study has expanded the phenotype in this syndrome by the observation of microcephaly, better characterization of skeletal abnormalities, less severe phenotype with only mild facial dysmorphisms and limb anomalies, as well as the absence of cleft mandible, which is a hallmark of the syndrome. Although the most frequent mutation in this study was the recurrent 16-repeat expansion in EIF4A3, there was an overrepresentation of the 14-repeat expansion, with mild phenotypic expression, thus suggesting that the number of these motifs could play a role in phenotypic delineation.

Experiences of a High-Risk Population with Prenatal Hemoglobinopathy Carrier Screening in a Primary Care Setting: a Qualitative Study.

Carrier screening for hemoglobinopathies (HbPs; sickle cell disease and thalassemia) aims to facilitate autonomous reproductive decision-making. In the absence of a Dutch national HbP carrier screening program, some primary care midwives offer screening on an ad hoc basis. This qualitative descriptive study explores how pregnant women perceive an offer of HbP carrier screening by their midwife. Semi-structured interviews (n = 26) were conducted with pregnant women at risk of being a HbP carrier, and whom were offered screening at their booking appointment in one of two midwifery practices in Amsterdam. The results showed that half of the respondents were familiar with HbPs. Generally, women perceived the offer of HbP carrier screening as positive, and most women (n = 19) accepted screening. Seven declined, of whom two already knew their carrier status. Important reasons to accept screening were to obtain knowledge about their own carrier status and health of their unborn child, and the ease of the procedure. A multistep process of decision-making was observed, as many women did not give follow-up testing (e.g. partner, invasive diagnostics) much consideration while deciding on accepting or declining HbP screening. Women experienced information overload, and preferred receiving the information at a different moment (e.g. before the intake by a leaflet, or preconceptionally). In conclusion, while prenatal HbP carrier screening is perceived as positive, informed decision-making seems to be suboptimal, and both the content and timing of the information provided needs improvement.

Cri du Chat syndrome: Characteristics of 73 Brazilian patients.

BACKGROUND: Cri du Chat syndrome (CdCS) is a genetic syndrome caused by deletions in the short arm of chromosome 5. Although the main clinical features of CdCS are well known, the neurocognitive and behavioural characteristics of the phenotype are rarely described in detail in the literature. In this study, we analysed the main phenotypic features of CdCS from a parental perspective. METHOD: A questionnaire was sent to 700 Brazilian families that were registered in the Brazilian Association of CdCS. The questions involved specific domains of CdCS, such as pregnancy and birth conditions, recurrence of the disease in the family, current major health problems, and aspects of cognitive development. RESULTS: In total, 73 questionnaires were completed: 44 females and 29 males, ranging from 9.5 months old to 40 years old (mean = 13.8 years; median = 12 years). Most of the parents noticed the typical cat-like cry at birth (94.4%). The age at diagnosis of CdCS ranged from the time of birth to 180 months (mean = 14 months; median = 6 months), while one case was diagnosed during pregnancy. In all of the cases, the diagnosis of CdCS was made by G-banding karyotype analysis. In 66.2% of the cases, the parents underwent cytogenetic investigation. A total of 52.1% of the parents answered that they did not remember what the recurrence risk of CdCS was in their family. The main health problems that were reported were as follows: swallowing problems (80.3%), feeding problems (80.3%), congenital heart disease (31.5%), spine abnormalities (28.8%), and neurological symptoms (20.5%), including seizures (11%). The behavioural problems that were reported were as follows: aggressive behaviour, stereotypies, anxiety, phobias, and genital manipulation/masturbation. Neurodevelopmental delay was reported in all of the cases. Independent walking was achieved in 72.2% of the patients. Approximately 50% of the patients never presented expressive language, and most of the patients are dependent on others for their daily activities. CONCLUSIONS: The questionnaire was a pioneer initiative in the CdCS support group, and the answers used in this study can improve the health care assistance to these patients because they focus attention on the demands from a parental perspective. In addition, nearly half of the families stated that they did not remember information regarding recurrence risk, which reinforces the importance of genetic counselling follow-up and the need for the expansion of genetic services in Brazil.

Factors for successful implementation of population-based expanded carrier screening: learning from existing initiatives.

Background: Carrier screening for autosomal recessive disorders aims to facilitate reproductive decision-making by identifying couples with a 1-in-4 risk in every pregnancy of having an affected child. Except for a few countries or regions, carrier screening is not widely offered and is mostly ancestry-based. Technological advances enable carrier screening for multiple diseases simultaneously allowing universal screening regardless of ancestry (population-based expanded carrier screening). It is important to study how this can be successfully implemented. This study therefore aims to identify critical factors involved in successful implementation, from a user perspective, by learning from already implemented initiatives. Methods: Factors associated with successful implementation were identified by: (i) a literature review and (ii) two case studies; studying experiences with carrier screening in two high-risk communities (a Dutch founder population and the Ashkenazi Jewish population), including a survey among community members. Results: Factors identified were familiarity with (specific) genetic diseases and its availability, high perceived benefits of screening (e.g. screening avoids much suffering), acceptance of reproductive options, perceived risk of being a carrier and low perceived social barriers (e.g. stigmatization). In contrast to the Jewish community, the initial demand for screening in the Dutch founder population did not entirely come from the community itself. However, the large social cohesion of the community facilitated the implementation process. Conclusion: To ensure successful implementation of population-based expanded carrier screening, efforts should be made to increase knowledge about genetic diseases, create awareness and address personal benefits of screening in a non-directive way.

Stakeholder perspectives on the implementation of genetic carrier screening in a changing landscape.

BACKGROUND: In most countries, genetic carrier screening is neither offered, nor embedded in mainstream healthcare. Technological developments have triggered a two-fold transition in carrier screening: the expansion from screening one single disorder to many disorders simultaneously, and offering screening universally, regardless of ancestry. This study aims to identify general and population-specific barriers and needs reflected by stakeholders regarding the implementation of carrier screening in a changing landscape. METHODS: Seventeen semi-structured interviews were conducted with Dutch key stakeholders working in the practical and scientific field of carrier screening. The constellation approach was used to categorise barriers and needs into three levels: culture, structure and practice. RESULTS: Barriers on a cultural level include: undecidedness about the desirability of carrier screening, and a lack of priority of screening in mainstream healthcare. On a structural level barriers included: need for organisational structures in healthcare for embedding carrier screening, need for guidelines, financial structures, practical tools for overcoming challenges during counselling, and a need for training and education of both professionals and the public. A lack of demand for screening by the public, and a need for a division of responsibilities were barriers on a practical level. CONCLUSION: The absence of a collective sense of urgency for genetic carrier screening, a lack of organisational structures, and uncertainty or even disagreement about the responsibilities seem to be important barriers in the implementation of carrier screening. Stakeholders therefore suggest that change agents should be formally acknowledged to strategically plan broadening of current initiatives and attune different stakeholders.

Short Communication Impact of early enzyme-replacement therapy for mucopolysaccharidosis VI: results of a long-term follow-up of Brazilian siblings.

Mucopolysaccharidosis type VI (MPS VI) is an autosomal recessive multisystem lysosomal storage disorder, which is characterized by the deficiency of the enzyme arylsulfatase B encoded by the ARSB gene. Treatment of this disease with enzyme-replacement therapy (ERT) improves the clinical status of and generates hope for MPS VI patients. However, only few reports on patients with MPS VI treated before 5 years of age have been published. Thus, the objective of this study was to compare the clinical parameters of two sisters affected by MPS VI who started ERT at different ages (9 years and 1 year 5 months, respectively) and to determine the most relevant clinical impacts of early treatment after 85 months of evaluation. The treatment was well tolerated by both siblings. ERT in the younger sibling resulted in increased growth, an improved 6-minute walk test, less coarse face, slower progression of cardiac valve disease, and the absence of compressive myelopathy compared to that in her older sister. On the other hand, the older sibling had typical MPS VI phenotypic features before the commencement of ERT. Corneal clouding, clawed hands, and progressive skeletal changes were observed in both siblings despite the treatment. Both siblings displayed reduced frequencies of upper respiratory infections and apnea indices. This study emphasizes that early diagnosis and treatment of MPS VI are critical for a better disease outcome and to enhance the quality of life for these patients.

Nager syndrome: confirmation of SF3B4 haploinsufficiency as the major cause.

Nager syndrome belongs to the group of acrofacial dysostosis, which are characterized by the association of craniofacial and limb malformations. Recently, exome sequencing studies identified the SF3B4 gene as the cause of this condition in most patients. SF3B4 encodes a highly conserved protein implicated in mRNA splicing and bone morphogenic protein (BMP) signaling. We performed SF3B4 sequencing in 14 families (18 patients) whose features were suggestive of Nager syndrome and found nine mutations predicted to result in loss-of-function. SF3B4 is the major gene responsible for autosomal dominant Nager syndrome. All mutations reported predict null alleles, therefore precluding genotype-phenotype correlations. Most mutation-negative patients were phenotypically indistinguishable from patients with mutations, suggesting genetic heterogeneity.

Case report. Johanson-Blizzard syndrome: a report of gender-discordant twins with a novel UBR1 mutation.

Johanson-Blizzard syndrome (JBS) is a rare autosomal recessive disorder resulting from loss-of-function mutations in the UBR1 gene. JBS can be easily recognized by its unique clinical presentation (including exocrine pancreatic insufficiency, hypoplasia/aplasia of the alae nasi, congenital scalp defects, sensorineural hearing loss, growth retardation, psychomotor retardation, and anal and genitourinary anomalies). The objective of this study is to report on the first familial case of gender-discordant twins presenting JBS and a novel mutation in the UBR1 gene. We also review literature describing molecularly confirmed cases of JBS. The female twin developed refractory severe diarrhea after the second month of life and died at the age of 3 months. The male twin also developed diarrhea and failure to thrive after the 3 month of life but improved when nutrition support and pancreatic enzyme replacement was started, and he has survived into adolescence. Both patients presented typical clinical features of JBS. A homozygous nonsense mutation (c.3682C>T; p.Q1228X) in UBR1 was confirmed. Severe presentation of JBS usually involves deleterious (nonsense, frameshift, or splice-site) mutations in the UBR1 gene that are thought to completely abolish the expression of a functional protein product, as in this familial case; however, milder presentation of JBS has occasionally been observed with missense mutations in at least 1 of the 2 copies of UBR1, in which there may be residual activity of the product of this gene. Early diagnosis and adequate treatment are crucial for a favorable outcome.

Haploinsufficiency of the human homeobox gene ALX4 causes skull ossification defects.

Inherited defects of skull ossification often manifest as symmetric parietal foramina (PFM; MIM 168500). We previously identified mutations of MSX2 in non-syndromic PFM and demonstrated genetic heterogeneity. Deletions of 11p11-p12 (proximal 11p deletion syndrome, P11pDS; MIM 601224) are characterized by multiple exostoses, attributable to haploinsufficiency of EXT2 and PFM. Here we identify ALX4, which encodes a paired-related homeodomain transcription factor, as the PFM disease gene in P11pDS.

CACP, encoding a secreted proteoglycan, is mutated in camptodactyly-arthropathy-coxa vara-pericarditis syndrome.

Altered growth and function of synoviocytes, the intimal cells which line joint cavities and tendon sheaths, occur in a number of skeletal diseases. Hyperplasia of synoviocytes is found in both rheumatoid arthritis and osteoarthritis, despite differences in the underlying aetiologies of the two disorders. We have studied the autosomal recessive disorder camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP; MIM 208250) to identify biological pathways that lead to synoviocyte hyperplasia, the principal pathological feature of this syndrome. Using a positional-candidate approach, we identified mutations in a gene (CACP) encoding a secreted proteoglycan as the cause of CACP. The CACP protein, which has previously been identified as both 'megakaryocyte stimulating factor precursor' and 'superficial zone protein', contains domains that have homology to somatomedin B, heparin-binding proteins, mucins and haemopexins. In addition to expression in joint synovium and cartilage, CACP is expressed in non-skeletal tissues including liver and pericardium. The similarity of CACP sequence to that of other protein families and the expression of CACP in non-skeletal tissues suggest it may have diverse biological activities.

Different conformation of two supernumerary 18p isochromosomes, one with a concomitant partial 18q trisomy.

The presence of a supernumerary 18p isochromosome is a rare chromosomal abnormality that results in 18p tetrasomy. This is a report on the clinical, cytogenetic and molecular findings of 2 non-related patients with a supernumerary 18p isochromosome. Both patients present some features of the 18p tetrasomy syndrome (strabismus, low-set ears, long and narrow fingers and toes), but additional characteristics were also observed. Cytogenetic analysis, FISH, MLPA and SNP array techniques showed that one of the isochromosomes is symmetric and monocentric, while the other is asymmetric and dicentric, yet resulting in a similar tetrasomy of the 18pter-18p10 region, followed by a partial 18q11.2 trisomy, an unprecedented finding in the literature.

Penile anthropometry in systemic lupus erythematosus patients.

The aim of this study was to evaluate penile anthropometry in systemic lupus erythematosus (SLE) patients compared with healthy controls and the possible relevant pubertal, clinical, hormonal and treatment factors that could influence penile dimensions. Twenty-five consecutive SLE patients were assessed by urological examination, sexual function, testicular ultrasound, hormones, sperm analysis, genetic analysis, clinical features and treatment. The control group included 25 age-matched healthy males. SLE patients had a lower median penis length and circumference [8 (7.5-10) vs. 10 (8-13) cm, p = 0.0001; 8 (7-10) vs. 10 (7-11) cm, p = 0.001; respectively], lower median testicular volume by right and left Prader [15 (10-25) vs. 20 (12-25) ml, p = 0.003; 15 (10-25) vs. 20 (12-25) ml, p = 0.006; respectively], higher median of follicle-stimulating hormone [5.8 (2.1-25) vs. 3.3 (1.9-9) IU/l, p = 0.002] and lower morning total testosterone levels (28% vs. 0%, p = 0.009) compared with controls. In spite of that, erectile dysfunction was not observed in patients or controls. Analyses of lupus patients revealed that the median penis circumference was lower in patients with disease onset before first ejaculation compared with those with disease onset after first ejaculation [7.8 (7-10) vs. 9.0 (7.5-10) cm, p = 0.026]. No differences were observed in the median penile anthropometry regarding sexual dysfunction (p = 0.610), lower morning total testosterone levels (p = 0.662), oligo/azoospermia (p = 0.705), SLE Disease Activity Index ≥ 4 (p = 0.562), Systemic Lupus International Collaborating Clinics/ACR Damage Index ≥ 1 (p = 0.478), prednisone cumulative dose (p = 0.789) and intravenous cyclophosphamide therapy (p = 0.754). Klinefelters syndrome (46XY/47XXY) was diagnosed in one (4%) SLE patient with decreased penile size whereas Y-chromosomal microdeletions was absent in all of them. In conclusion, we have identified reduced penile dimensions in SLE patients with no deleterious effect in erectile function. Disease onset before first ejaculation seems to affect penis development in pre-pubertal lupus.

A description of adaptive and maladaptive behaviour in children and adolescents with Cri-du-chat syndrome.

BACKGROUND: Psychological tests can be useful to record adaptive and maladaptive behaviours of children with intellectual disability. The objective of this study was to describe the adaptive and maladaptive behaviour of children and adolescents with Cri-du-chat syndrome. METHODS: The sample consisted of 10 children and adolescents with Cri-du-chat syndrome (mean chronological age=11.3 years, mean mental age=18 months). The developmental quotient was calculated through the Psychoeducational Profile - Revised. An observational protocol was used to record adaptive and maladaptive behaviours. RESULTS: The number of maladaptive behaviours observed was different among participants. However, all of them had high rates of adaptive behaviours, such as rule-following. CONCLUSIONS: These results, though preliminary, justify that we continue to think about the need for psychoeducational interventions aimed at stimulating the repertoire of adaptive behaviours, in people with Cri-du-chat syndrome.

Angiokeratoma: a cutaneous marker of Fabry's disease.

The initial symptoms of Fabry's disease (FD) may seem harmless and may delay its diagnosis. A survey and screening for FD were performed on men with biopsy-proven angiokeratoma and some of their relatives (n = 29). Three patients were identified. Dermatologists should be aware of this prominent early feature and investigate unexplained cutaneous vascular lesions to detect FD.

Chromosome imbalances in syndromic hearing loss.

The cause of hearing impairment has not been elucidated in a large proportion of patients. We screened by 1-Mb array-based comparative genomic hybridization (aCGH) 29 individuals with syndromic hearing impairment whose clinical features were not typical of known disorders. Rare chromosomal copy number changes were detected in eight patients, four de novo imbalances and four inherited from a normal parent. The de novo alterations define candidate chromosome segments likely to harbor dosage-sensitive genes related to hearing impairment, namely 1q23.3-q25.2, 2q22q23, 6p25.3 and 11q13.2-q13.4. The rare imbalances also present in normal parents might be casually associated with hearing impairment, but its role as a predisposition gene remains a possibility. Our results show that syndromic deafness is frequently associated with chromosome microimbalances (14-27%), and the use of aCGH for defining disease etiology is recommended.

Clinical and biochemical studies in mucopolysaccharidosis type II carriers.

The aim of the study was to characterize clinically and biochemically mucopolysaccharidosis type II (MPS II) heterozygotes. Fifty-two women at risk to be a carrier, with a mean age of 34.1 years (range 16-57 years), were evaluated through pedigree analysis, medical history, physical examination, measurement of iduronate sulfatase (IDS) activities in plasma and in leukocytes, quantification of glycosaminoglycans (GAGs) in urine, and analysis of the IDS gene. Eligibility criteria for the study also included being 16 years of age or older and being enrolled in a genetic counselling programme. The pedigree and DNA analyses allowed the identification of 40/52 carriers and 12/52 non-carriers. All women evaluated were clinically healthy, and their levels of urinary GAGs were within normal limits. Median plasma and leukocyte IDS activities found among carriers were significantly lower than the values found for non-carriers; there was, however, an overlap between carriers' and non-carriers' values. Our data suggests that MPS II carriers show lower plasma and leukocyte IDS activities but that this reduction is generally associated neither with changes in levels of urinary GAGs nor with the occurrence of clinical manifestations.

Genomic imbalances associated with mullerian aplasia.

BACKGROUND: Aplasia of the müllerian ducts leads to absence of the uterine corpus, uterine cervix, and upper (superior) vagina. Patients with müllerian aplasia (MA) often exhibit additional clinical features such as renal, vertebral and cardiac defects. A number of different syndromes have been associated with MA, and in most cases its aetiology remains poorly understood. OBJECTIVE AND METHODS: 14 syndromic patients with MA and 46,XX G-banded karyotype were screened for DNA copy number changes by approximately 1 Mb whole genome bacterial artificial chromosome (BAC) array based comparative genomic hybridisation (CGH). The detected alterations were validated by an independent method and further mapped by high resolution oligo-arrays. RESULTS: Submicroscopic genomic imbalances affecting the 1q21.1, 17q12, 22q11.21, and Xq21.31 chromosome regions were detected in four probands. Presence of the alterations in the normal mother of one patient suggests incomplete penetrance and/or variable expressivity. CONCLUSION: 4 of the 14 patients (29%) were found to have cryptic genomic alterations. The imbalances on 22q11.21 support recent findings by us and others that alterations in this chromosome region may result in impairment of müllerian duct development. The remaining imbalances indicate involvement of previously unknown chromosome regions in MA, and point specifically to LHX1 and KLHL4 as candidate genes.