Schizophrenia (SZ) is a group of chronic mental disorders, which is often accompanied by perception, thinking, emotion, behavior and other impairments. MRI techniques can be used to investigate brain structural and functional alterations in SZ, so as to provide significant support for the recognition of biomarkers for mental disorders. Structural and functional brain networks in SZ constructed with multimodal MRI have been analyzed by the human brain connectome using graph theory in numerous studies, which highlighted the abnormality of brain complex networks, such as increased shortest path length, decreased clustering coefficient and global efficiency, as well as deficits of global hub, providing further support for the hypothesis of dysconnection in SZ. The recent advancements of structural networks, functional networks and multimodal networks were reviewed, and the characteristics of brain complex networks in SZ were explored, the existing problems of analysis methods and future direction were discussed in this paper.

Objective To establish a noninvasive prenatal testing(NIPT) method based on the chromosome specific site sequencing instead of the conventional whole genome sequencing.Methods Blood plasma samples from 200 pregnant women with known fetus karyotypes were collected.First,the specific loci on chromosome 13,18 and 21 were selected by the database filter.Then,these specific loci were captured by probes,and were performed sequencing.Finally,chromosome aneuploidy was identified by the Z-score.ResultsSeven fetuses with 21-trisomy syndrome,3 with 18-trisomy syndrome and 1 with 13-trisomy syndrome were detected by the chromosome specific site sequencing,and the results were accordant with those of the whole genome sequencing method.Conclusion The NIPT method based on the chromosome specific site sequencing has the advantages of low cost and high throughput,which may replace the NIPT method based on the whole genome sequencing.

OBJECTIVE To analyze the data of non-invasive prenatal testing based on specific loci of circulating cell-free fetal DNA (cffDNA). METHODS Selected loci of target chromosomes were analyzed by sequence capture and sequencing. Meanwhile, 600 loci were selected from other chromosomes for determining the concentration of cffDNA. RESULTS A total of 768 specific loci were captured on chromosomes 21 and 18, and used to determine whether the two were abnormal. When the minimum concentration of detected cffDNA was set at 3% and the threshold of Z score was set to [-6,6], the specificity of the analysis was 99.37% and the sensitivity was 100%. CONCLUSION A reliable, convenient and low-cost analytical method has been developed. The method requires less sequencing data for non-invasive prenatal testing, and can accurately detect abnormalities of fetal chromosomes 21 and 18, and simultaneously determine the concentration of cffDNA.

Objective:To explore the clinical application of preimplantation genetic testing for monogenic disorders (PGT-M) in an unique case with Spinal muscular atrophy (SMA) type 2+ 0.Methods:A special SMA family presented at the Third Affiliated Hospital of Guangzhou Medical University on October 19, 2020 was selected as the study subject. Multiple ligation-dependent probe amplification (MLPA) and molecular tagging linkage analysis were carried out to identify the SMN1 genotype of the couple and their fetus. Subsequently, next-generation sequencing (NGS), molecular tagging linkage analysis, and chromosomal microarray analysis were employed to determine the haplotypes and validate the result of PGT-M on the 11 embryos derived for the couple. Results:The female partner was identified as a carrier of the rare SMN1[2+ 0] variant, and prenatal diagnosis confirmed the fetus to be affected by SMA. Ultimately, PGT-M has successfully selected four embryos free from the pathogenic SMN1 variants and X chromosome deletion. Conclusion:PGT-M can effectively prevent the transmission of rare genetic variants such as the SMA 2+ 0 subtype in the families. Above finding has provided guidance for genetic counseling and family planning for the couple.