Cytognetic and Molecular Genetic Study of Transient Abnormal Myelopoiesis

1995 Fiscal Year Final Research Report Summary

• Project/Area Number: 06454609
• Research Category: Grant-in-Aid for General Scientific Research (B)
• Allocation Type: Single-year Grants
• Research Field: Human genetics
• Research Institution: Nagasaki University
• Principal Investigator: NIKAWA Norio Nagasaki University, School of Medicine Professor, 医学部, 教授 (00111170)
• Co-Investigator(Kenkyū-buntansha): JINNO Yoshihiro Nagasaki University, School of Medicine Lecturer, 医学部, 講師 (20179097)
• Project Period (FY): 1994 – 1995
• Keywords: Transient leukemia / Down syndrome / Breakpoint analysis / Positional cloning / Gene isolation / Chromosome inversion / Cosmid contig / Tumor-related gene

Research Abstract

Transient abnormal myclopoiesis (TAM) is a leukemoid reaction occurring occasionally in Down syndrome (DS) newborn infants. It has been hypothesized that "disomic homozygosity" in 21-trisomic cells plays an important-role in the genesis of TAM,and the putative TAM gene was suggested to be mapped at a 21q11 region. We encountered a DS-associated TAM infant with a 47, XY,inv (21) (q11.1q22.13), +inv (21) (q11.1q22.13) karyotype. Based on another presumption that in this patient, the putative TAM gene is disrupted by the break, we tried to isolate a breakpoint DNA.FISH analysis with cosmid clones corresponding to various STS markers mapped at around 21q11.1-q11.2, we confirmed that the proximal breakpoint of the inv (21) was located between two STSs, G51E07 and D21S215, the latter locus being consistent to the previous tentative mapping. After construction of a cosmid contig encompassing between the 2 markers, we have isolated a cosmid clone corresponding to the proximal breakpoint of the inversion. This breakpoint was located nearby a previously identified duplicated-region that is homologous to the sequence at 21q22.1. The isolated cosmid clone is useful for analysis of other TAM patients and for a search for a transcript at or flanking the breakpoint.

Research Products

• [Publications] Ohta T, Nakano M, Tsujita T, Abe K, Osoegawa K,Yamagata T, Yoshiura K, Jinno Y, Soeda E, Niikawa N: "Isolation of a cosmid clone corresponding to a region of thr inv(21)breakpoint in a patient with transient abnormal myelopoiesis." American Journal of Human Genetics. 58. 544-550 (1996)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Ohta T,Nakano M,Tsujita T,Abe K,Osoegawa K,Yamagata T,Yoshiura K,Jinno Y,Soeda E,Niikawa N: "Isolation of a cosmid clone corrsponding to a region of the inv (21) breakpoint in a patient with transient abnormal myelopoicsis." Am J Hum Genet. 58. 544-550 (1996)
  • Description: 「研究成果報告書概要(欧文)」より