Topic
Ring chromosome
About: Ring chromosome is a research topic. Over the lifetime, 1546 publications have been published within this topic receiving 31061 citations. The topic is also known as: supernumerary circular chromosome.
Papers published on a yearly basis
Papers
More filters
TL;DR: A ring chromosome 2 mosaic was found in a newborn female with severe intrauterine growth retardation (IUGR), postnatal growth failure, and a few minor abnormalities, which indicates that the chromosome abnormality arose after conception.
Abstract: A ring chromosome 2 mosaic [46,XX/46,XX,r(2)(p25q37)] was found in a newborn female with severe intrauterine growth retardation (IUGR), postnatal growth failure, and a few minor abnormalities. Psychomotor development has been normal to 19 months old. A ring chromosome 2 is present in 77.8% of the nuclei examined and is not found in the parents or a sibling. G- and R-banding reveal the break points to be p25q37. The presence of a normal cell line indicates that the chromosome abnormality arose after conception.
11 citations
TL;DR: Data suggest that the PEP A locus was lost in ring formation in a fibroblast clone 46, XX, r(l 8) and that the line with the ring chromosome predominates in blood lymphocytes.
Abstract: A young girl with 46, XX, r(18)/46, XX/45, XX, –18 chromosome constitution is reported. She displays a slight degree of mental retardation. The line with the ring chromosome predominates in blood lymphocytes. In skin fibroblast culture the ring(18) line showed a constant decreasing trend, from 45% at the first passage, down to its disappearance at the 19th passage, where only 46, XX cells were observed. The child/mid parents' ratio of Peptidase A activity in red cells was 0.36. The Peptidase A activity in a fibroblast clone 46, XX, r(l 8) was 0.55 compared to the 46, XX line. These data suggest that the PEP A locus was lost in ring formation.
11 citations
TL;DR: This case, along with 14 previously reported cases, indicate that the smallest critical region for chromosome 13 microcephaly is 109,743,729-144,110,721.
Abstract: A ring chromosome 13 or r(13) exhibits breakage and reunion at breakage points on the long and short arms of chromosome 13, with deletions of the chromosomal segments distal to the breakage points. The r(13) chromosome accounts for approximately 20% of ring chromosomes compatible with life. We describe a female patient with mental retardation, growth retardation, microcephaly, craniofacial dysmorphy, hearing impairment, and prolonged prothrombin time. Chromosomal analysis via GTG banding of peripheral blood lymphocytes revealed a karyotype of 46,XX,r(13)(p13q34)[71]/45,XX,-13[12]/ 46,XX,dic r(13;13)(p13q34;p13q34)[9]/46,XX,-13,+mar[5]/47, XX,+r(13) (p13q34)x2[2]/46,XX[1] at the age of 6 years and 46,XX,r(13)(p13q34)[82]/45,XX,-13[14]/46,XX,dic r(13;13)(p13q34; p13q34)[2]/46,XX, -13,+mar[2]. Array comparative genomic hybridization analysis of the blood demonstrated a 4.37-Mb deletion on chromosome 13q [arr cgh 13q34q34(109,743,729-144,110,721)]. A cytogenetic study of peripheral blood revealed a rare chromosomal abnormality associated with different cell lines that included structural and numerical abnormalities of chromosome 13. This case, along with 14 previously reported cases, indicate that the smallest critical region for chromosome 13 microcephaly is 109,743,729-144,110,721.
11 citations
TL;DR: It is demonstrated that the chromosome composition of a neoplasia can be identified more systematically and accurately using these combined molecular cytogenetic approaches.
11 citations
TL;DR: Oc- casional polyploid cells were apparent, in which, de-pending on the number of chromosomes, two or more monocentric or dicentric ring chromosomes were ob-served.
Abstract: Previously the occurrence of a D ring chromosome replacing a D chromosome has been reported in 15 cases (Wang et al., 1962; Bain and Gauld, 1963; Turner, 1963; Macintyre et al., 1964; Reisman, Darnell, and Murphy, 1965; Adams, 1965; Jacobsen, 1966; Gerald et al., 1967; Teplitz et al., 1967; Gilgenkrantz, Peters, and Streiff, 1967; Sparkes, Carrel, and Wright, 1967; Lejeune et al., 1968; Mikkelsen and Niebuhr, 1969). A collection of the physical findings in patients with ring chromosomes is of special interest, to see whether there is a correlation between clinical signs and certain chromosomal anomalies.
11 citations