ABSTRACT
<p><b>OBJECTIVE</b>To identify the genetic cause for a 11-year-old Chinese boy with Meier-Gorlin syndrome (MGS).</p><p><b>METHODS</b>Chromosomal microarray analysis (CMA) was used to detect potential variations, while whole exome sequencing (WES) was used to identify sequence variants. Sanger sequencing was used to confirm the suspected variants.</p><p><b>RESULTS</b>The boy has featured short stature, microtia, small patella, slender body build, craniofacial anomalies, and small testes with normal gonadotropin. A complete uniparental disomy of chromosome 16 was revealed by CMA. WES has identified a novel homozygous mutation c.67A>G (p.Lys23Glu) in ORC6 gene mapped to chromosome 16. As predicted by Alamut functional software, the mutation may affect the function of structural domain of the ORC6 protein.</p><p><b>CONCLUSION</b>The patient is probably the first diagnosed MGS case in China, who carried a novel homozygous mutation of the ORC6 gene and uniparental disomy of chromosome 16. The effect of this novel mutation on the growth and development needs to be further investigated.</p>
Subject(s)
Child , Humans , Male , Base Sequence , Chromosomes, Human, Pair 16 , Genetics , Congenital Microtia , Genetics , Family Health , Fathers , Growth Disorders , Genetics , Heterozygote , Micrognathism , Genetics , Mutation , Origin Recognition Complex , Genetics , Patella , Congenital Abnormalities , Polymerase Chain Reaction , Methods , Sequence Analysis, DNA , Methods , Uniparental Disomy , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To explore the expression of origin recognition complex 1 (ORC1) during the DNA replication of vascular muscle cells (VSMC).</p><p><b>METHODS</b>VSMC of thoracic aorta in rats were obtained by the adherence method of tissue culture. The cell synchrony was obtained by the method of double-thymidine block, colchicine treatment and serum starvation. The expression of ORC1 mRNA at different cell cycles of VSMC was determined by RT-PCR and the protein expression of ORC1 was analyzed by Western blot.</p><p><b>RESULTS</b>Cultured VSMC were identified by light microscope and immunocytochemistry. Significant expression of ORC1 mRNA and protein in a quiescent stage of VSMC were not observed. Upon synchronization, the expression of ORC1 mRNA was significantly higher at G(1)/S phase of VSMC than that at S and G(2)/M phases. The expression of ORC1 protein followed same changes as the ORC1 mRNA expression at different stages of cell cycles.</p><p><b>CONCLUSION</b>ORC1 may be an important regulatory factor at the initiation of proliferative process of VSMC.</p>