Application of eight-probe fluorescence in situ hybridization and R-banding karyotype analysis for the diagnosis of acute lymphoblastic leukemia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the value of eight-probe fluorescence in situ hybridization (FISH) and R-banding karyotype analysis for the diagnosis of acute lymphoblastic leukemia (ALL).</p><p><b>METHODS</b>With the eight-probe FISH (using probes for MYC, P16, E2A, CHIC2/D10Z1/D17Z1, TEL/AMLl, MLL, BCR/ABL1, and IGH) and R-banding karyotype analysis, 237 cases of ALL were analyzed.</p><p><b>RESULTS</b>Cytogenetic changes were detected in 135 (56.96%) of all cases, which have involved MYC, P16, E2A, CHIC2/D10Z1/D17Z1, TEL/AMLl, MLL, BCR/ABL1, and IGH polyploidies. R-banding karyotype analysis has only detected abnormalities in 48 of such cases, in addition with 14 abnormalities missed by the FISH probes, which have given a total positive rate of 26.16%. The detection rate of the two methods has differed significantly(P<0.05).</p><p><b>CONCLUSION</b>Compared with the R-banding karyotype analysis, the eight-probe FISH is more accurate and efficient. Diagnosis of cytogenetic abnormalities for children with ALL using the combined method can provide a basis for evaluation of prognosis as well as personalized therapy.</p>

Morphology and pathogenesis of 47, XYY/47, XY, +mar identified in patients with super male syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the source and morphology of supernumerary markers from patients with 47,XYY/47,XY, +mar and supermale syndrome.</p><p><b>METHODS</b>Conventional GTG banded karyotyping and dual-color fluorescence in situ hybridization (FISH) were performed on 21 such patients.</p><p><b>RESULTS</b>Among these cases, 18 had their small supernumerary marker derived from the Y chromosome. Three were derived from autosomal chromosomes. Those derived from Y chromosome were small fragments with centromeres, while those derived from autosomes were in the ring form.</p><p><b>CONCLUSION</b>In children with supermale syndrome and 47,XYY/47,XY,+ mar, the supernumerary marker chromosomes primarily derive from sex chromosomes. These small chromosomes mainly have the forms of small segments with centromeres or rings. For such children, molecular cytogenetic analysis can facilitate genetic counseling and prenatal diagnosis.</p>

A novel splicing mutation in COL1A1 gene caused type I osteogenesis imperfecta in a Chinese family / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study a family affected with osteogenesis imperfecta for potential mutations in COL1A1 gene.</p><p><b>METHODS</b>Clinical data of an affected family was collected. Potential mutation of the COL1A1 gene was screened using polymerase chain reaction and direct sequencing. Suspected mutation was detected in 20 unaffected relatives and 200 unrelated healthy controls.</p><p><b>RESULTS</b>Analysis of RNA splicing has revealed a c.3208G/A mutation, which created a new splice sites and led to a frameshift mutation. The same mutation was not detected in the unaffected relatives or the 200 healthy controls.</p><p><b>CONCLUSION</b>Mutations of the COL1A1 gene are one of the major causes of osteogenesis imperfecta in Chinese population. Our finding has enriched the mutation spectrum of type I collagen genes.</p>

Identification of a novel splicing mutation in COL1A1 gene in a Chinese family affected with typeⅠosteogenesis imperfecta / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the genetic cause for a large family affected with typeⅠosteogenesis imperfecta.</p><p><b>METHODS</b>Genomic DNA was extracted from peripheral venous blood samples. The entire coding region and intron-exon boundaries of the COL1A1 gene were subjected to PCR amplification and direct sequencing. Total RNA was also extracted from immortalized B cell lines from the patients, with the first strand of cDNA synthesized with an oligo(dT)18 primer. The PCR products were directly sequenced using the TA cloned plasmid.</p><p><b>RESULTS</b>A c.3208G>A mutation has been identified in the COL1A1 gene, which can alter the splicing pattern of mRNA.</p><p><b>CONCLUSION</b>A novel splicing mutation c.3208G>A of the COL1A1 gene probably underlies the disease.</p>