In this study, the risk of birth defects was increased with IVF but was no longer significant after adjustment for maternal factors. The risk of birth defects associated with intracytoplasmic sperm ...injection remained higher after multivariate adjustment. Residual confounding cannot be ruled out.
Consistent evidence from individual studies, including registry-based cohort studies
1
,
2
and meta-analyses, has linked assisted conception involving in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) with an increased risk of birth defects.
3
–
8
The associations between the use of these techniques and birth defects have appeared to be stronger for singleton births than for multiple births.
9
,
10
It is unclear whether the excess of birth defects after IVF or ICSI may be attributable to patient characteristics related to infertility,
8
rather than to the treatment, and whether the risk is similar across assisted reproductive technologies and related therapies.
3
,
11
, . . .
Small nuclear RNAs (snRNAs) are essential factors in messenger RNA splicing. By means of homozygosity mapping and deep sequencing, we show that a gene encoding U4atac snRNA, a component of the minor ...U12-dependent spliceosome, is mutated in individuals with microcephalic osteodysplastic primordial dwarfism type I (MOPD I), a severe developmental disorder characterized by extreme intrauterine growth retardation and multiple organ abnormalities. Functional assays showed that mutations (30G>A, 51G>A, 55G>A, and 111G>A) associated with MOPD I cause defective U12-dependent splicing. Endogenous U12-dependent but not U2-dependent introns were found to be poorly spliced in MOPD I patient fibroblast cells. The introduction of wild-type U4atac snRNA into MOPD I cells enhanced U12-dependent splicing. These results illustrate the critical role of minor intron splicing in human development.
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a lethal inherited arrhythmia syndrome characterized by adrenergically stimulated ventricular tachycardia. Mutations in the cardiac ...ryanodine receptor gene (RYR2) cause an autosomal dominant form of CPVT, while mutations in the cardiac calsequestrin 2 gene (CASQ2) cause an autosomal recessive form.
The aim of this study was to clinically and genetically evaluate a large family with severe autosomal dominant CPVT.
Clinical evaluation of family members was performed, including detailed history, physical examination, electrocardiogram, exercise stress test, and autopsy review of decedents. We performed genome-wide linkage analysis in 12 family members and exome sequencing in 2 affected family members. In silico models of mouse and rabbit myocyte electrophysiology were used to predict potential disease mechanisms.
Severe CPVT with dominant inheritance in 6 members was diagnosed in a large family with 2 sudden deaths, 2 resuscitated cardiac arrests, and multiple appropriate implantable cardioverter-defibrillator shocks. A comprehensive analysis of cardiac arrhythmia genes did not reveal a pathogenic variant. Exome sequencing identified a novel heterozygous missense variant in CASQ2 (Lys180Arg) affecting a highly conserved residue, which cosegregated with disease and was absent in unaffected family members. Genome-wide linkage analysis confirmed a single linkage peak at the CASQ2 locus (logarithm of odds ratio score 3.01; θ = 0). Computer simulations predicted that haploinsufficiency was unlikely to cause the severe CPVT phenotype and suggested a dominant negative mechanism.
We show for the first time that a variant in CASQ2 causes autosomal dominant CPVT. Genetic testing in dominant CPVT should include screening for heterozygous CASQ2 variants.
Epidemiologic Associations With Cerebral Palsy O'CALLAGHAN, Michael E; MACLENNAN, Alastair H; GIBSON, Catherine S ...
Obstetrics and gynecology (New York. 1953),
09/2011, Letnik:
118, Številka:
3
Journal Article
Recenzirano
To estimate epidemiologic risk factors for cerebral palsy.
Data were collected by linkage to state-based perinatal repositories and cerebral palsy registers and using a maternal questionnaire. The ...cohort included 587 individuals with cerebral palsy and 1,154 non-cerebral palsy controls.
The following factors were associated with cerebral palsy: recorded maternal infection during pregnancy (41.4% patients compared with 31.3% controls; odds ratio OR 1.55, 95% confidence interval 1.26-1.91), small for gestational age (birth weight less than third customized centile 43.9% patients compared with 6.3% controls; OR 11.75, 6.25-22.08), gestational age less than 32 weeks (29.3% patients compared with 0.7% controls; OR 59.20, 28.87-121.38), multiple birth (OR 6.62, 4.00-10.95), a relative with cerebral palsy (OR 1.61, 1.12-2.32), breech position (13.7% patients compared with 6.0% controls; OR 2.48, 1.76-3.49), bleeding at any time in pregnancy (29.3% patients compared with 16.9% controls; OR 2.04, 1.61-2.58), male sex (58.8% patients compared with 45.8% controls; OR 1.68, 1.38-2.06), multiple miscarriage (7.7% patients compared with 3.5% controls; OR 2.30, 1.38-3.82), smoking (14.0% patients compared with 10.6% controls; OR 1.37, 1.02-1.85), and illicit drug use (3.3% patients compared with 1.5% controls; OR 2.22, 1.14-4.30). Factors not associated with cerebral palsy were "disappearing twin," diabetes, maternal body mass index, hypertension, alcohol consumption, anemia, maternal hypothyroidism, forceps or vacuum delivery, and maternal age.
Preterm birth, intrauterine growth restriction, perinatal infection, and multiple birth present the largest risks for a cerebral palsy outcome. Reassuringly, upper respiratory tract and gastrointestinal infections during pregnancy were not associated with cerebral palsy.
II.
Individuals with the three base pair deletion NM_000267.3(NF1):c.2970_2972del p.(Met992del) have been recognised to present with a milder neurofibromatosis type 1 (NF1) phenotype characterised by ...café-au-lait macules (CALs) and intertriginous freckling, as well as a lack of cutaneous, subcutaneous and plexiform neurofibromas and other NF1-associated complications. Examining large cohorts of patients over time with this specific genotype is important to confirm the presentation and associated risks of this variant across the lifespan. Forty-one individuals with the in-frame NF1 deletion p.Met992del were identified from 31 families. Clinicians completed a standardised clinical questionnaire for each patient and the resulting data were collated and compared to published cohorts. Thirteen patients have been previously reported, and updated clinical information has been obtained for these individuals. Both CALs and intertriginous freckling were present in the majority of individuals (26/41, 63%) and the only confirmed features in 11 (27%). 34/41 (83%) of the cohort met NIH diagnostic criteria. There was a notable absence of all NF1-associated tumour types (neurofibroma and glioma). Neurofibroma were observed in only one individual-a subcutaneous lesion (confirmed histologically). Nineteen individuals were described as having a learning disability (46%). This study confirms that individuals with p.Met992del display a mild tumoural phenotype compared to those with 'classical', clinically diagnosed NF1, and this appears to be the case longitudinally through time as well as at presentation. Learning difficulties, however, appear to affect a significant proportion of NF1 subjects with this phenotype. Knowledge of this genotype-phenotype association is fundamental to accurate prognostication for families and caregivers.
A 57‐year‐old man with a family history of aortic aneurysm was found, during assessment of unexplained fever, to have an infrarenal aortic aneurysm requiring immediate repair. Dilatation of popliteal ...and iliac arteries was also present. Progressive aortic root dilatation with aortic regurgitation was documented from 70 years leading to valve‐sparing aortic root replacement at 77 years, at which time genetic studies identified a likely pathogenic FBN1 missense variant c.6916C > T (p.Arg2306Cys) in exon 56. The proband's lenses were normally positioned and the Marfan syndrome (MFS) systemic score was 0/20. Cascade genetic testing identified 15 other family members with the FBN1 variant, several of whom had unsuspected aortic root dilatation; none had ectopia lentis or MFS systemic score ≥ 7. Segregation analysis resulted in reclassification of the FBN1 variant as pathogenic. The combination of thoracic aortic aneurysm and dissection (TAAD) and a pathogenic FBN1 variant in multiple family members allowed a diagnosis of MFS using the revised Ghent criteria. At 82 years, the proband's presenting abdominal aortic aneurysm was diagnosed retrospectively to have resulted from IgG4‐related inflammatory aortopathy.
TIMMDC1 encodes the Translocase of Inner Mitochondrial Membrane Domain-Containing protein 1 (TIMMDC1) subunit of complex I of the electron transport chain responsible for ATP production. We studied a ...consanguineous family with two affected children, now deceased, who presented with failure to thrive in the early postnatal period, poor feeding, hypotonia, peripheral neuropathy and drug-resistant epilepsy. Genome sequencing data revealed a known, deep intronic pathogenic variant TIMMDC1 c.597-1340A>G, also present in gnomAD (~1/5000 frequency), that enhances aberrant splicing. Using RNA and protein analysis we show almost complete loss of TIMMDC1 protein and compromised mitochondrial complex I function. We have designed and applied two different splice-switching antisense oligonucleotides (SSO) to restore normal TIMMDC1 mRNA processing and protein levels in patients' cells. Quantitative proteomics and real-time metabolic analysis of mitochondrial function on patient fibroblasts treated with SSOs showed restoration of complex I subunit abundance and function. SSO-mediated therapy of this inevitably fatal TIMMDC1 neurologic disorder is an attractive possibility.
Background: Genetic testing in clinical trials introduces several ethical and logistical issues to discuss with potential participants when taking informed consent. The aim of this study was to ...explore the attitudes of healthy volunteers in phase 1 studies to the topics of genetic security, genetic privacy and incidental genetic findings.
Methods: Healthy volunteers presenting for screening appointments at a phase 1 clinical trial unit (CMAX Clinical Research, Adelaide, Australia) took an anonymous paper survey about genetic testing.
Results: There were 275 respondents to the survey. The mean age was 27 years (range 18-73); 54% were male and 53% were of North/Western European ethnicity. Just over half the healthy volunteers thought genetic security (56%) and genetic privacy (57%) were "important" or "very important". However, the security of their genetic information was ranked less important than other personal information, including mobile phone number, internet browser search history and email address. Two-thirds of respondents would trade genetic privacy for re-identifiability if information relevant to their health were discovered by genetic testing. Healthy volunteers favoured the return of incidental genetic findings (90% indicated this was "important" or "very important"). A level of risk (10 to 90%) for developing a serious medical condition that would "trigger" the return of incidental genetic findings to participants was not identified.
Conclusions: Healthy volunteers screening for phase 1 clinical trials have mixed views about the importance of genetic security and genetic privacy, but they strongly favour the return of incidental genetic findings that could affect their health. These issues should be discussed with potential participants during informed consent for phase 1 clinical trials with genetic testing.
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