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Background: Low-temperature severely limits the growth and development of Camellia oleifera (C. oleifera). The mitogen-activated protein kinase (MAPK) cascade plays a key role in the response to cold stress. Methods and results: Our study aims to identify MAPK cascade genes in C. oleifera and reveal their roles in response to cold stress. In our study, we systematically identified and analyzed the MAPK cascade gene families of C. oleifera, including their physical and chemical properties, conserved motifs, and multiple sequence alignments. In addition, we characterized the interacting networks of MAPKK kinase (MAPKKK)-MAPK kinase (MAPKK)-MAPK in C. oleifera. The molecular mechanism of cold stress resistance of MAPK cascade genes in wild C. oleifera was analyzed by differential gene expression and real-time quantitative reverse transcription-PCR (qRT-PCR). Conclusion: In this study, 21 MAPKs, 4 MAPKKs and 55 MAPKKKs genes were identified in the leaf transcriptome of C. oleifera. According to the phylogenetic results, MAPKs were divided into 4 groups (A, B, C and D), MAPKKs were divided into 3 groups (A, B and D), and MAPKKKs were divided into 2 groups (MEKK and Raf). Motif analysis showed that the motifs in each subfamily were conserved, and most of the motifs in the same subfamily were basically the same. The protein interaction network based on Arabidopsis thaliana (A. thaliana) homologs revealed that MAPK, MAPKK, and MAPKKK genes were widely involved in C. oleifera growth and development and in responses to biotic and abiotic stresses. Gene expression analysis revealed that the CoMAPKKK5/CoMAPKKK43/CoMAPKKK49—CoMAPKK4—CoMAPK8 module may play a key role in the cold stress resistance of wild C. oleifera at a high-elevation site in Lu Mountain (LSG). This study can facilitate the mining and utilization of genetic resources of C. oleifera with low-temperature tolerance. [ABSTRACT FROM AUTHOR]

Objective: To carry out prenatal screening and diagnosis for a woman with advanced maternal age., Methods: Non-invasive prenatal testing (NIPT) was carried out to determine the risk of fetal chromosome aneuploidy. Aminiocentesis was proceeded for fetal chromosomal karyotyping and copy number variation sequencing (CNV-seq). The fetus was subjected to systematic ultrasound screening in the second trimester., Results: NIPT has indicated there was a loss of fetal sex chromosome. Karotyping of the amniocyte showed a mosaic sex chromosome abnormality 45,X[53]/46,X,+mar[7]. The result of fetal DNA CNV-seq was seq[GRCh37]del(Yq11.1q12) chrY: g.13 104 553-28 819 361del, seq[GRCh37]del(Yp11.32p11.2) chrY: g.10 001-9 873 915del (mosaic ratio: 30%). Ultrasonography discovered that the fetus had renal dysplasia and male external genitalia. The karyotypes of the couple were both normal., Conclusion: Multiple genetic tests should be carried out for fetus with a high risk for chromosome aneuploidies signaled by NIPT. It is difficult to predict the post-natal phenotype for fetuses with mosaic sex chromosomal aneuploidies. The couple should be carefully counseled upon genetic counseling.

Objective: To delineate the nature and origin of chromosomal copy number variants (CNVs) in a boy with mental retardation and multiple congenital malformation., Methods: The karyotypes of the patient and his parents were analyzed with routine G-banded chromosomal analysis. Genome DNA was analyzed by next generation sequencing (NGS)., Results: The patient was found to harbor a structural aberration involving chromosome 3p. The karyotype of his father was 46,XY,t(3;7)(p26;q31), while his mother was found to be normal. NGS analysis of the patient revealed a 2.16 Mb microdeletion at 3p26.3-pter and a duplication at 7q31.33-qter., Conclusion: The structural aberration of 3p carried by the patient has derived from his father whom carried a balanced translocation of t(3;7), and his karyotype was finally determined as 46,XY,der(3) t(3;7)(p26.3;q31.33)pat. The abnormal phenotype of the patient can probably be attributed to the presence of 3p26.3-pter microdeletion and 7q31.33-qter duplication.