Clinical characteristics and genetic analysis of two children with Autosomal dominant mental retardation type 21 due to variants of CTCF gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical and genetic characteristics of two children with developmental delay.@*METHODS@#Two children who had presented at the Children's Hospital Affiliated to Shandong University on August 18, 2021 were enrolled as the study subjects. Clinical and laboratory examination, chromosomal karyotyping and high-throughput sequencing were carried out for both children.@*RESULTS@#Both children had a 46,XX karyotype. High-throughput sequencing showed that they have respectively carried a c.489delG (p.Q165Rfs*14) and a c.1157_1158delAT (p.Y386Cfs*22) frameshifting variant of the CTCF gene, both had a de novo origin and were unreported previously.@*CONCLUSION@#The CTCF gene variants probably underlay the development delay in the two children. Above discovery has enriched the mutational spectrum of the CTCF gene and has important implications for revealing the genotype-phenotype correlation for similar patients.

Analysis of clinical and genetic characteristics of a child with ring chromosome 4 syndrome / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a child featuring short stature.@*METHODS@#G-banded karyotyping, chromosomal microarray analysis (CMA) and high-throughput sequencing were carried out on peripheral blood sample from the child.@*RESULTS@#The karyotype of the child was ascertained as 45,XY,-4[3]/46,XY,r(4)(p16q35)[84]/47,XY,-4,r(4)(p16q25)*2[7]/48,XY,-4,r(4)(p16q35)*3[1]/46,XY,dic r(4;4)(p16q35;p16q35)[2]/46,XY,add(4)(p16)[3]. A 647 kb deletion at 4p16.3 was identified by CMA, which encompassed 6 OMIM genes including ZNF141, PIGG, PDE6B, ATP5I, PCGF3 and MYL5. High-throughput sequencing has identified no pathogenic/likely pathogenic variants consistent with the clinical symptoms.@*CONCLUSION@#A rare ring chromosome 4 syndrome was identified by combined chromosomal karyotyping, CMA and high-throughput sequencing. Conventional cytogenetic analysis and genetic testing in combine have enabled the diagnosis in this case.

Molecular cytogenetic analysis of a case with ring chromosome 3 syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the genetic cause for a child with developmental delay and congenital heart disease through molecular cytogenetic analysis.</p><p><b>METHODS</b>G-banded karyotyping and chromosomal microarray analysis (CMA) were performed for the patient and his parents.</p><p><b>RESULTS</b>The proband's karyotype was detected as ring chromosome 3, and a 3q26.3-25.3 deletion encompassing 45 genes has been found with CMA. Testing of both parents was normal.</p><p><b>CONCLUSION</b>Clinical phenotype of the patient with ring chromosome 3 mainly depends on the involved genes. It is necessary to combine CMA and karyotyping for the diagnosis of ring chromosome, as CMA can provide more accurate information for variations of the genome.</p>