Non-genetic Cases Research Articles

Breaching Confidentiality in Genetic and Non-Genetic Cases: Two Problematic Distinctions.

Ethical questions about confidentiality arise when patients refuse to inform relatives who are at risk of a genetic condition. Specifically, healthcare providers may struggle with the permissibility of breaching confidentiality to warn patients' at-risk relatives. In exploring this issue, several authors have converged around the idea that genetic cases differ from non-genetic cases (e.g., involving a threat of violence or the spread of an infectious disease) along two related dimensions: (1) In genetic cases, the risk of harm is already present in an at-risk third party, whereas in non-genetic cases, it is not; and (2) In genetic cases, the patient does not create a risk of harm to a third party, whereas in non-genetic cases, the patient does. I argue that these distinctions do not exclusively differentiate genetic from non-genetic cases and should not bear on the permissibility of breaching confidentiality. Instead, such determinations should be based on other considerations.

Evaluating the monogenic contribution and genotype-phenotype correlation in patients with isolated thoracic aortic aneurysm.

Thoracic aortic aneurysm with or without dissection (TAAD) can be broadly categorized as syndromic TAAD (sTAAD) and isolated TAAD (iTAAD). sTAAD and is highly correlated with genetics. However, although the incidence of iTAAD is much higher, its monogenic contribution is not yet clear. Here, we sequenced 15 known TAAD genes for 578 iTAAD cases from four cardiac centers in China and found that 10.6% patients with a pathogenic/likely pathogenic (P/LP) variant. Other 7.27% of patients carried variants of uncertain significance in these target genes. We further investigated the correlations among genetics, clinical features, and long-term outcomes. Genetic patients showed younger onset ages (P = 1.31E-13) and larger aortic diameter (P = 1.00E-6), with the youngest age in patients with FBN1 P/LP variants. Monogenic variants were also associated with more aortic segments involved (P = 0.043) and complicated with initial dissection (P = 4.50E-5), especially for genetic patients with non-FBN1 P/LP variants. MACEs occurred in 14.9% patients during follow-up of median 55 months. Genetic status (P = 0.001) and initial dissection (P = 3.00E-6) were two major risk factors for poor prognosis. Early onset age was associated with MACEs in non-genetic cases without initial dissection (P = 0.005). Our study revealed the monogenic contribution in known TAAD genes to iTAAD patients. The genotype-phenotype correlations may complement the risk stratification of iTAAD patients and identification of higher risk subgroups, as well as assist the development of tailored precision medicine in iTAAD.

Molecular Study of Childhood Steroid-Resistant Nephrotic Syndrome: A Hospital-Based Study.

Steroid-resistant nephrotic syndrome (SRNS) patients with genetic mutations most commonly have histology of focal segmental glomerulosclerosis (FSGS) and do not respond to immunosuppressive drugs. We report the molecular screening results of 18 pediatric SRNS cases presented to our nephrology clinic. Three pathogenic variants have been detected, two previously reported and one novel variant. The reported pathogenic variants have been detected in NPHS1 and NPHS2 genes. A novel pathogenic variant has been detected in the inverted formin 2 gene ( INF2 ) gene. We did not detect any variant of the WT1 gene. There were 13 males. Mean age of study participants at enrollment was 69 months. There were 12 cases of primary SRNS. The mean duration from onset of symptoms to SRNS diagnosis was 13 months. FSGS and minimal change disease (MCD) were present in the same number of cases. The response rate (complete or partial) to immunosuppressive drugs was seen in only one patient in the genetic SRNS group ( n = 3), while the response rate in nongenetic cases ( n = 15) was 80%. Two nonresponders in the genetic SRNS group had FSGS for histopathology and pathogenic variants (NPHS2 and INF2). The other three nonresponders in the nongenetic SRNS group had both FSGS ( n = 1) and MCD ( n = 2) histopathology. There were two deaths in the study cohort of the nongenetic SRNS group. This study highlights the screening of the SRNS cohort by a panel of extended genes rather focussing on the three most common genes ( NPHS1 , NPHS2 , and WT1 ). This further confirms the molecular etiology of SRNS in three cases and extends the list of pathogenic variants of genetic SRNS in the North Indian population. This is the first study in the eastern part of Uttar Pradesh in India.

Cranial irradiation in childhood mimicking neurofibromatosis type II.

Neurofibromatosis type II (NF2) is a genetic disease characterized by bilateral vestibular schwannomas (VS) and other nerve system tumors. However, such tumors may be associated with environmental, rather than a genetic, etiology. Individuals fulfilling the clinical criteria of NF2 who had been treated by head ionized irradiation at a young age were compared for disease characteristics and molecular analysis with non-irradiated sporadic NF2 cases. In the study cohort, three of 33 sporadic adult cases fulfilling NF2 diagnostic criteria had a history of early age cranial irradiation exposure. None of the irradiated patients had bilateral VS compared with 73.3% of the non-irradiated individuals. One of the irradiated patients had no VS, while none of the non-irradiated NF2 cases had absence of VS. All of the irradiated individuals had brain meningiomas and thyroid tumors compared with 47% and 0%, respectively, of the non-irradiated individuals. Molecular analyses for NF2 mutations in blood of the irradiated individuals failed to detect disease-causing mutations. This study suggest that environmental factors may mimic NF2. Identifying such non-genetic cases fulfilling clinical criteria of the genetic disease may be crucial for the purposes of genetic counseling and patient management.

Association of brain amyloidosis with pro-inflammatory gut bacterial taxa and peripheral inflammation markers in cognitively impaired elderly

The pathway leading from amyloid-β deposition to cognitive impairment is believed to be a cornerstone of the pathogenesis of Alzheimer's disease (AD). However, what drives amyloid buildup in sporadic nongenetic cases of AD is still unknown. AD brains feature an inflammatory reaction around amyloid plaques, and a specific subset of the gut microbiota (GMB) may promote brain inflammation. We investigated the possible role of the GMB in AD pathogenesis by studying the association of brain amyloidosis with (1) GMB taxa with pro- and anti-inflammatory activity; and (2) peripheral inflammation in cognitively impaired patients. We measured the stool abundance of selected bacterial GMB taxa (Escherichia/Shigella, Pseudomonas aeruginosa, Eubacterium rectale, Eubacterium hallii, Faecalibacterium prausnitzii, and Bacteroides fragilis) and the blood expression levels of cytokines (pro-inflammatory cytokines: CXCL2, CXCL10, interleukin [IL]-1β, IL-6, IL-18, IL-8, inflammasome complex (NLRP3), tumor necrosis factor-alpha [TNF-α]; anti-inflammatory cytokines: IL-4, IL-10, IL-13) in cognitively impaired patients with (n = 40, Amy+) and with no brain amyloidosis (n = 33, Amy−) and also in a group of controls (n = 10, no brain amyloidosis and no cognitive impairment). Amy+ patients showed higher levels of pro-inflammatory cytokines (IL-6, CXCL2, NLRP3, and IL-1β) compared with both controls and with Amy− patients. A reduction of the anti-inflammatory cytokine IL-10 was observed in Amy+ versus Amy−. Amy+ showed lower abundance of E. rectale and higher abundance of Escherichia/Shigella compared with both healthy controls (fold change, FC = −9.6, p < 0.001 and FC = +12.8, p < 0.001, respectively) and to Amy− (FC = −7.7, p < 0.001 and FC = +7.4, p = 0.003). A positive correlation was observed between pro-inflammatory cytokines IL-1β, NLRP3, and CXCL2 with abundance of the inflammatory bacteria taxon Escherichia/Shigella (rho = 0.60, p < 0.001; rho = 0.57, p < 0.001; and rho = 0.30, p = 0.007, respectively) and a negative correlation with the anti-inflammatory E. rectale (rho = −0.48, p < 0.001; rho = −0.25, p = 0.024; rho = −0.49, p < 0.001). Our data indicate that an increase in the abundance of a pro-inflammatory GMB taxon, Escherichia/Shigella, and a reduction in the abundance of an anti-inflammatory taxon, E. rectale, are possibly associated with a peripheral inflammatory state in patients with cognitive impairment and brain amyloidosis. A possible causal relation between GMB-related inflammation and amyloidosis deserves further investigation.

Productive performance of indigenous and HF crossbred dairy cows in Gondar, Ethiopia

Aim: To study the magnitude of variation in lactation length (LL), lactation milk yield (LMY) and peak-yield (PY)due to genetic and non-genetic cases in indigenous and crossbred cattle reared under private dairy unit in and around Gondar, Ethiopia. Materials and Methods: The study was conducted on 411 milch animals from 86 dairy farmers comprising of 172 indigenous and 239 Holstein-Friesian (HF) crossbred cows. These cows were maintained under farmer's management system in and around Gondar (Ethiopia) and were analyzed by Least squares analysis to study the magnitude of variation in their LL, LMY and PY due to genetic and some non-genetic factors. Result: The overall Least squares means for LL, LMY and PY were estimated to be 275.1165.23 days, 1407.3471.34 litres and 6.880.38 litres respectively. Genetic group and lactation order had significant effect (P0.01) on LL, LMY and PY. Season of calving had significant effect (P0.01) on LMY and PY but its effect on LL was non-significant. Effect of location of herd was significant (P0.05) on LMY and PY while its effect on LL was non-significant. Variations in all the traits due to herd size and farming system were statistically non-significant. Conclusion: Productive performance of dairy cows in this study was found to be lesser than the optimum values desirable for profitable milk production.

A metabolic basis for fibromyalgia and its related disorders: the possible role of resistance to thyroid hormone

It has long been recognized that the symptom complex of fibromyalgia can be seen with hypothyroidism. Hypothyroidism may been categorized, like diabetes, into type I (hormone deficient) and type II (hormone resistant). Most cases of fibromyalgia fall into the latter category. The syndrome is reversible with treatment, and is usually of late onset. It is likely more often acquired than due to mutated receptors. Now that there is evidence to support the hypothesis that fibromyalgia may be due to thyroid hormone resistance, four major questions appear addressable. First, can a simple biomarker be found to help diagnose it? Second, what other syndromes similar to Fibromyalgia may share a thyroid-resistant nature? Third, in non-genetic cases, how is resistance acquired? Fourth, what other methods of treatment become available through this new understanding? Preliminary evidence suggests that serum hyaluronic acid is a simple, inexpensive, sensitive, and specific test that identifies fibromyalgia. Overlapping symptom complexes suggest that chronic fatigue syndrome, Gulf war syndrome, premenstrual syndrome, post traumatic stress disorder, breast implant silicone sensitivity syndrome, bipolar affective disorder, systemic candidiasis, myofascial pain syndrome, and idiopathic environmental intolerance are similar enough to fibromyalgia to merit investigation for possible thyroid resistance. Acquired resistance may be due most often to a recently recognized chronic consumptive coagulopathy, which itself may be most often associated with chronic infections with mycoplasmids and related microbes or parasites. Other precipitants of thyroid resistance may use this or other paths as well. In addition to experimentally proven treatment with supraphysiologic doses of thyroid hormone, the thyroid-resistant disorders might be treatable with anti-hypercoagulant, anti-infective, insulin-sensitizing, and hyaluronolytic strategies.

GENETICS OF DUPUYTREN’S DISEASE

The striking variation in prevalence, approaching 30% in individuals over the age of 60 years in Norway, is strong evidence for an inherited susceptibility to Dupuytren's disease. In many pedigrees, inheritance appears to follow the autosomal dominant model. Other modes of inheritance are consistent with the data, however, and it remains unclear whether the many apparently sporadic cases have a genetic basis. The inherited susceptibility may influence tissue's sensitivity to the effects of environmental exposures. High prevalence, late age of onset, and the possibility of nongenetic cases are features of Dupuytren's disease that complicate genetic studies, as can be seen from estimates of relative risk. Identification of susceptibility loci is a worth-while goal as it may throw entirely new light on the nature of Dupuytren's disease and ultimately may open avenues to new treatments.