Psychiatric Genetics最新文献

Background: Metachromatic leukodystrophy (MLD) is a lysosomal storage disorder caused by the deficiency of arylsulfatase A (ARSA). Accumulation of sulfatide, substrate of ARSA, in the central and peripheral nervous system causes neurodegeneration, which leads to neurologic and psychiatric symptoms. Adult-onset MLD is the least frequent type of MLD and shows both genetic and clinical heterogeneity. The clinical presentation differs according to pathogenic variants in the ARSA gene. Therefore, establishing genotype-phenotype correlation is crucial for the diagnosis and management of patients with adult-onset MLD.

Methods: A family of multiple individuals with adult-onset psychomotor deterioration was assessed. The patients had behavioral disturbances initially, and neurological deficits had developed in the later stages of the disease. The family was analyzed using karyotype analysis, Sanger sequencing, custom next-generation sequencing (NGS) panel of the genes related to dementia, and whole exome sequencing (WES).

Results: Karyotype analysis and NGS dementia panel showed no pathogenic aberration. However, WES analysis revealed heterozygous variants in the ARSA gene: c.542T>G (p.Ile181Ser) and c.661T>A (p.Phe221Ile). Segregation analysis, performed by Sanger sequencing, showed that all individuals with the same clinical findings were compound heterozygous for c.542T>G and c.661T>A substitutions.

Conclusion: The compound heterozygosity of c.542T>G and c.661T>A variants of the ARSA gene cause adult-onset MLD. The genotype detected in the patients was not reported before in the literature. Moreover, the clinical course of the patients followed a similar pattern with dominantly psychiatric symptoms at the initial stage of the disease, indicating a distinct phenotype caused by the two pathogenic variants of the ARSA gene.

Although psychotic symptoms have occasionally been associated with pathogenic CHD2 variants, few articles have provided phenotypic information in this respect or described treatment response. We describe an 18-year-old female with a 15q26.1 interstitial deletion that disrupts CHD2, who at age 12 developed a variety of psychotic symptoms that responded well to quetiapine therapy. She also exhibited improvement in her cognitive functioning, language skills, and social responsiveness, which coincided with the initiation of metformin. This is only the third report to characterize antipsychotic treatment response in an individual harboring a pathogenic CHD2 variant, and the first to do so in relation to quetiapine. Although anecdotal, psychotic symptoms that develop in relation to pathogenic CHD2 variants may respond to atypical antipsychotic therapy, and metformin may have additional benefits in this population with respect to behavioral/social deficits. However, more evidence is needed before any firm conclusions can be drawn.

Heterozygous variants in the Early B cell factor 3 ( EBF3 ) have been reported in individuals presenting with hypotonia, ataxia and delayed development syndrome (HADDS) (MIM#617330). However, individuals with pathogenic variants in EBF3 show phenotypic heterogeneity and very few variants in the C-terminal domain have been described. We report on a heterozygous de-novo variant in the EBF3 gene in an individual with neurodevelopmental delay and behavioural problems. The proband presented with speech delay, learning disability and behavioural problems that suggest an oppositional defiant disorder. He also has hyperactivity, irritability, hetero-aggressiveness, visual hallucinations, insomnia and decreased pain sensitivity. Whole exome sequencing revealed a de-novo heterozygous nonsense variant - c.1408C>T (p.Arg470*) - in the EBF3 gene, classified as pathogenic. The patient herein described, with a truncating variant in the C-terminal domain of EBF3 , supports the clinical variability of this condition and contributes to genotype-phenotype correlation of this rare disorder.

Background: Copy number variants (CNVs) are an important source of normal and pathogenic genome variations. Chromosomal microdeletions and microduplications have long been associated with abnormal developmental outcomes. Recently, the application of CNV sequencing (CNV-seq) is rapidly identifying new recurrent microdeletion and microduplication syndromes and a previously unsuspected level of copy number variation which needs to be distinguished from pathogenic change.

Materials and methods: In this research, a 26-year-old, gravida 1, para 0, woman underwent amniocentesis at 18 weeks of gestation. Cytogenetic analysis of the cultured amniocytes and CNV-seq on uncultured amniocytes was performed. After that, we performed trio whole-exome sequencing (WES) on the family.

Results: CNV-seq detected three chromosomal microduplications in the fetus, respectively are 2p16.1p15, 6q27, and 9p22.3. The microduplication of 2p16.1p15 is inherited from the mother, and the microduplication of 6q27 and 9p22.3 comes from the father. After genetic counseling, the parents decided to continue the pregnancy.

Conclusion: We present a rare case of a Chinese family with inherited multiple chromosomal microduplications with normal phenotype. Our case can be helpful for prenatal diagnosis and genetic counseling. Chromosomal microdeletions and microduplications are difficult to detect by conventional cytogenetics. Combination of prenatal ultrasound, karyotype analysis, CNV-seq, trio-WES, and genetic counseling is helpful for the prenatal diagnosis of chromosomal microdeletions/microduplications.

Although numerous copy number variants (CNVs) are considered pathogenic with respect to the development of schizophrenia, only eight loci have reached genome-wide significance. Reviews/studies characterizing antipsychotic use in this context exist for only three corresponding CNV syndromes. As these disorders also predispose to neurodevelopmental anomalies and various medical comorbidities, affected individuals may be particularly sensitive to the side effects of antipsychotic medications. As such, this review sought to identify and describe all reports of antipsychotic use among individuals with the other genome-wide significant schizophrenia risk CNVs (2p16.3 deletions/ NRXN1 variants, 15q13.3 and 16p11.2 deletions, 7q11.23 duplications, and 1q21.1 deletions or duplications). Only 10 eligible articles describing 29 individuals were included. While treatment response was reasonably good for most individuals, despite variability existing across the specific CNV syndromes, side effects were rarely reported. Above all, this review highlights the need for more case reports/series to be published.

Objective: Schizophrenia is a long-term neurological condition that impacts the quality of life of patients. To explore the expression of miR-20b-5p in schizophrenia, to analyze the diagnostic role of miR-20b-5p in schizophrenia, and to demonstrate that miR-20b-5p affects the progression of schizophrenia.

Methods: The expression of miR-20b-5p was detected by real-time quantitative PCR. The diagnostic role of miR-20b-5p in schizophrenia was analyzed by receiver operating characteristic (ROC) curves. A schizophrenic rat model was constructed by injecting MK-801, and anxiety and cognition in schizophrenic rats were evaluated by an open-field test, novel object recognition test, and Morris water maze test.

Results: The expression level of miR-20b-5p was decreased in individuals with schizophrenia, and it could serve as a potential biomarker for the diagnosis of schizophrenia. In addition, miR-20b-5p affected anxiety-like and cognitive behavior in schizophrenic rats.

Conclusion: miR-20b-5p may inhibit the progression of schizophrenia.

Chromosome 19q13 microdeletion syndrome is a rare genetic disorder characterized by prenatal and postnatal growth retardation, intellectual disability, expressive language impairment, ectodermal dysplasia, and slender habitus. We present a 20-year-old female with hypermetamorphosis, punding, and frangophilia, initially misdiagnosed as schizophrenia. A neuropsychiatric clinical reevaluation of the case led to a diagnosis of melancholic depression and severe intellectual developmental delay. Cerebral MRI revealed hypoplasia of the frontal lobes and cerebellar vermis. Genetic testing at the age of 6 years revealed a 46 XX karyotype with an interstitial deletion of the long arm of chromosome 19 - del(19)(q13.11q13.13). The specific genetic defect, together with the cerebral abnormalities, was considered to be the cause of the unusual psychopathology. Every case of psychosis requires a comprehensive medical workup, as schizophrenia is one of the most commonly mimicked syndromes in medicine.

Background: Major depressive disorder (MDD) is among the leading causes of disability worldwide and treatment efficacy is variable across patients. Polymorphisms in cytochrome P450 2C19 (CYP2C19) play a role in response and side effects to medications; however, they interact with other factors. We aimed to predict treatment outcome in MDD using a machine learning model combining CYP2C19 activity and nongenetic predictors.

Methods: A total of 1410 patients with MDD were recruited in a cross-sectional study. We extracted the subgroup treated with psychotropic drugs metabolized by CYP2C19. CYP2C19 metabolic activity was determined by the combination of *1, *2, *3, and *17 alleles. We tested if treatment response, treatment-resistant depression, and side effects could be inferred from CYP2C19 activity in combination with clinical-demographic and environmental features. The model used for the analysis was based on a decision tree algorithm using five-fold cross-validation.

Results: A total of 820 patients were treated with CYP2C19 metabolized drugs. The predictive performance of the model showed at best.70 accuracy for the classification of treatment response (average accuracy = 0.65, error = ±0.047) and an average accuracy of approximately 0.57 across all the tested outcomes. Age, BMI, and baseline depression severity were the main features influencing prediction across all the tested outcomes. CYP2C19 metabolizing status influenced both response and side effects but to a lower extent than the previously indicated features.

Conclusion: Predictive modeling could contribute to precision psychiatry. However, our study underlines the difficulty in selecting variables with sufficient impact on complex outcomes.