Detection of MYCN amplification in three neuroblastoma cell lines by non-radioactive chromosomal in situ hybridization.

A non-radioactive chromosomal in situ hybridization technique utilizing a biotin-streptavidin-polyalkaline-phosphatase complex was successfully applied to three neuroblastoma cell lines for detection of MYCN amplification. These cell lines, designated PER-106, PER-107, and PER-108, were derived from consecutive bone marrow samples taken from a patient with stage IV neuroblastoma. The cell line derived at diagnosis (PER-106) exhibited MYCN amplification in the form of variable numbers of double-minute chromosomes, small fragments, and rings of varying sizes.

Chromosomal localization of amplified N-myc in neuroblastoma cells using a biotinylated probe.

G-banded chromosome analysis of neuroblastoma cells from two children revealed homogeneously staining regions (hsr) in one patient and double minutes (dmin) in the other. Subsequently, both abnormalities were confirmed as areas of N-myc amplification using chromosomal in situ hybridization with a biotinylated N-myc probe. In addition, the first patient's karyotype contained a possible derivative chromosome 17, which was also demonstrated to contain amplified N-myc, indicating the presence of an hsr unidentified by G-banding.

A chromosomal study of workers with long-term exposure to radio-frequency radiation.

Objective: To examine whether an increased level of chromosome damage occurs in the stimulated lymphocytes of radio-linemen after long-term but intermittent exposure to radio-frequency radiation (RFR) during the course of their work.

Design And Participants: Chromosome studies were performed on blood samples from 38 radio-linemen matched by age with 38 controls, all of whom were employed by Telecom Australia. The radio-linemen had all worked with RFR in the range 400 kHz-20 GHz with exposures at or below the Australian occupational limits, and the controls were members of the clerical staff who had no exposure to RFR.