A comparison of GC content and the proportion of Alu/Kpnl-repetitive sequences in a single dark- and light-band region from a human chromosome

Journal Article · Mon Mar 14 23:00:00 EST 1994 · Genomics; (United States)

DOI:https://doi.org/10.1006/geno.1994.1160· OSTI ID:7062365

Yoshiura, Koh-Ichiro; Kubota, Takeo; Soejima, Hidenobu; Tamura, Toshiya; Izumikawa, Yoshinori; Niikawa, Norio; Jinno, Yoshihiro ^[1]

---

1. Nagasaki Univ. School of Medicine (Japan)

To obtain direct evidence for a molecular basis of differentiation between regular Giemsa dark (G)- and light (R)-band regions of human chromosomes, two regions of chromosome 11, q14-q22 (G-band) and q23-q25 (R-band), were microdissected. The DNA fragments were amplified by the linker-primer polymerase chain reaction and cloned into pUC19. Microclones from each library were then compared by colony hybridization with repetitive DNA sequences, by Southern blot hybridization of each microclone to total human genomic DNA and mouse-human hybrid cell DNA containing only human chromosome 11, and by sequencing of unique and Alu-repetitive clones. Among the G-band-derived microclones analyzed, 43.0% were single-copy (unique) sequences and 23.2% contained highly repetitive sequence elements; in the R-band-derived library, 54.2% were unique clones and 20.3% had highly repetitive elements. The G-band library was significantly richer in clones positive for KpnI sequences (4.1% in the G-band library vs 2.8% in the R-band library). No significant difference was found in the proportion of Alu repetitive clones present in the two libraries, but Class IV Alu sequence derivatives were more frequently observed in the R-library than in the G-library. Sequence analysis revealed no significant difference in GC content or in the ratio of CpG sequence to GpC dinucleotide between 30 microclones derived from G-bands and 29 microclones derived from R-bands. This study has provided direct evidence for the relative GC contents and the proportions of Alu and KpnI families in both a G-band and an R-band of a human chromosome and also has demonstrated the usefulness of microdissection and microcloning for obtaining region-specific DNA sequence data. 24 refs., 2 figs., 6 tabs.

• OSTI ID: 7062365
• Journal Information: Genomics; (United States), Journal Name: Genomics; (United States) Vol. 20:2; ISSN GNMCEP; ISSN 0888-7543
• Country of Publication: United States
• Language: English

Related Subjects

550400* -- Genetics
59 BASIC BIOLOGICAL SCIENCES
AMINES
AROMATICS
AZAARENES
AZINES
BANDING TECHNIQUES
CHROMOSOMES
CLONING
CYTOLOGICAL TECHNIQUES
CYTOSINE
DNA HYBRIDIZATION
DNA SEQUENCING
DNA-CLONING
GUANINE
HETEROCYCLIC COMPOUNDS
HUMAN CHROMOSOMES
HYBRIDIZATION
HYDROXY COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PURINES
PYRIMIDINES
STRUCTURAL CHEMICAL ANALYSIS