Genetic Association of Lipids and Lipid-Lowering Drug Target Genes With Attention Deficit Hyperactivity Disorder.

BACKGROUND: Lipid metabolism plays an essential role in nervous system development. Cholesterol deficiency leads to a variety of neurodevelopmental disorders, such as autism spectrum disorder and fragile X syndrome. There have been a lot of efforts to search for biological markers associated with and causal to ADHD, among which lipid is one possible etiological factor that is quite widely studied. We aimed to evaluate the causal relationship between lipids traits, lipid-lowering drugs, and attention deficit hyperactivity disorder (ADHD) outcomes using Mendelian randomization (MR) studies. METHODS: We used summary data from genome-wide association studies to explore the causal relationships between circulating lipid-related traits and ADHD. Then, quantitative trait loci for the expression of lipid-lowering drug target genes and genetic variants associated with lipid traits were extracted. Summary-data-based MR and inverse-variance-weighted MR (IVW-MR) were used to investigate the correlation between the expression of these drug-target genes and ADHD. RESULTS: After rigorous screening, 939 instrumental variables were finally included for univariable mendelian randomization analysis. However, there is no correlation between lipid profile and ADHD risk. Drug target analysis by IVW-MR method observed that APOB-mediated low-density lipoprotein cholesterol was associated with lower ADHD risk (odds ratio [OR] = 0.90, 95% confidence interval [CI] [0.84, 0.97]; p = .007), whereas LPL-mediated triglycerides levels were associated with a higher risk of ADHD (OR = 1.13, 95% CI [1.06, 1.21]; p < .001). CONCLUSION: Our results suggest that APOB gene and LPL gene may be candidate drug target genes for the treatment of ADHD.

Development and validation of a nomogram for predicting severe respiratory syncytial virus-associated bronchiolitis.

BACKGROUND: Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis and is related to the severity of the disease. This study aimed to develop and validate a nomogram for predicting severe bronchiolitis in infants and young children with RSV infection. METHODS: A total of 325 children with RSV-associated bronchiolitis were enrolled, including 125 severe cases and 200 mild cases. A prediction model was built on 227 cases and validated on 98 cases, which were divided by random sampling in R software. Relevant clinical, laboratory and imaging data were collected. Multivariate logistic regression models were used to determine optimal predictors and to construct nomograms. The performance of the nomogram was evaluated by the area under the characteristic curve (AUC), calibration ability and decision curve analysis (DCA). RESULTS: There were 137 (60.4%) mild and 90 (39.6%) severe RSV-associated bronchiolitis cases in the training group (n = 227) and 63 (64.3%) mild and 35 (35.7%) severe cases in the validation group (n = 98). Multivariate logistic regression analysis identified 5 variables as significant predictive factors to construct the nomogram for predicting severe RSV-associated bronchiolitis, including preterm birth (OR = 3.80; 95% CI, 1.39-10.39; P = 0.009), weight at admission (OR = 0.76; 95% CI, 0.63-0.91; P = 0.003), breathing rate (OR = 1.11; 95% CI, 1.05-1.18; P = 0.001), lymphocyte percentage (OR = 0.97; 95% CI, 0.95-0.99; P = 0.001) and outpatient use of glucocorticoids (OR = 2.27; 95% CI, 1.05-4.9; P = 0.038). The AUC value of the nomogram was 0.784 (95% CI, 0.722-0.846) in the training set and 0.832 (95% CI, 0.741-0.923) in the validation set, which showed a good fit. The calibration plot and Hosmer‒Lemeshow test indicated that the predicted probability had good consistency with the actual probability both in the training group (P = 0.817) and validation group (P = 0.290). The DCA curve shows that the nomogram has good clinical value. CONCLUSION: A nomogram for predicting severe RSV-associated bronchiolitis in the early clinical stage was established and validated, which can help physicians identify severe RSV-associated bronchiolitis and then choose reasonable treatment.

Case report: Altered pre-mRNA splicing caused by intronic variant c.1499 + 1G > A in the SLC4A4 gene.

Proximal renal tubular acidosis (pRTA) with ocular abnormalities is an autosomal recessive disease caused by variants in the Solute Carrier Family 4 Member 4 (SLC4A4) gene. Patients present with metabolic acidosis and low plasma bicarbonate concentration (3∼17 mmol/L). In addition, they are often accompanied by ocular abnormalities, intellectual disability, and growth retardation. The patient underwent whole exome sequencing (WES) and bioinformatics analysis of variant pathogenicity in this study. Then, a minigene assay was conducted to analyze the splicing site variant further. Compound heterozygous variants in the SLC4A4 gene (NM_003759.3), c.145C > T (p.Arg49*) and c.1499 + 1G > A, were detected by WES. The minigene assay showed an mRNA splicing aberration caused by the c.1499 + 1G > A variant. Compared with the wild type, the mutant type caused 4-base insertion between exons 10 and 11 of SLC4A4 after expression in HEK293 cells. In conclusion, the c.1499 + 1G > A variant in the SLC4A4 gene may be one of the genetic causes in the patient. Moreover, our study provides the foundation for future gene therapy of such pathogenic variants.

Beware of missed diagnosis in patients with multiple genetic diseases: a case report.

BACKGROUND: Duchenne muscular dystrophy (DMD) is an X-linked recessive inherited disorder caused by the absence of the Dystrophin protein. Cerebral cavernous malformations (CCMs) are the most common vascular abnormalities in the central nervous system caused by the absence of the products of the CCM genes. Most CCMs cases reported occurring in a sporadic form are often asymptomatic. CASE PRESENTATION: We report a rare case of a 7-year-old Chinese boy with a co-existing DMD and sporadic CCMs. We found classic clinical features of DMD and non-specific pathological changes in his brain. We made the definitive diagnosis based on the results of whole-exome sequencing (WES), a repeat from exon 3 to exon 9 of the DMD inherited from his mother, and a de novo heterozygote nonsense mutation C.418G > T of the PDCD10 exon 6. CONCLUSION: We should take care to avoid missed diagnoses in patients with multiple genetic disorders.