1. STUDY OF THE CHROMOSOMAL CONTITUTION OF NORMAL HUMANS AND THE EFFECT OF LOW DOSES OF RADIATION.
2. CYTOGENETIC STUDY OF ABNORMAL GENOMES PARTICULARLY IN CELLS CARRYING A SUSPECTED ERROR IN THE REPAIR OF DNA.
A large collaborative study, involving almost all French cytogenetics laboratories, has been carried out to study pericentric inversion existing in the human population. The whole sample comprised of 305 independent cases, most of which have previously been unpublished.
A study has been made of the chromosomal constitution of normal humans, and the effects of low doses of radiation, as well as a cytogenetic study of abnormal genomes, particularly in cells carrying a suspected error in the repair of deoxyribonucleic acid (DNA).
PROJECT 1: STUDY OF THE CHROMOSOMAL CONDITION OF NORMAL HUMANS AND THE EFFECT OF LOW DOSES OF RADIATION.
THE FIRST POINT WILL BE TO ANALYSE, USING TH R BAND METHOD, A THOUSAND (OR SO) KARYOTYPES PRESENT IN A CERTAIN NUMBER OF NORMAL INDIVIDUALS. AFTER CULTURE OF BLOOD LYMPHOCYTES, THE STAINED MITOSES WILL BE PHOTOGRAPHED AND ANALYSED BY TWO INDEPENDENT OBSERVERS. ALL THE ABNOMALIES DETECTED WILL BE COUNTED IN ORDER TO KNOW, AS PRECISELY AS POSSIBLE, THE SPONTANEOUS RATE. SUBJECTS OF DIFFERENT AGE AND SEX WILL BE ANALYSED.
THE SECOND POINT WILL BE TO USE THE SAME BLOOD SAMPLES FOR GAMMA-IRRADIATION AT DOSES FROM 0.05 - 0.50 GRAY. THE MITOSES OBTAINED AFTER CULTURE WILL THEN BE STUDIED AS IN THE PREVIOUS EXPERIMENT WHICH WILL SERVE AS A CONTROL. THIS PIECE OF RESEARCH SHOULD PERMIT PRECISE QUANTIFICATION OF ANOMALIES INDUCED BY LOW RADIATION DOSES AND MAY ALSO PERMIT QUALITATIVE DIFFERENTIATION OF ANOMALIES INDUCED BY RADIATION AND THOSE WHICH OCCUR "SPONTANEOUSLY".
PROJECT 2: CYTOGENETIC STUDY OF ABNORMAL GENOMES PARTICULARLY IN CELLS CARRYING A SUSPECTED ERROR IN THE REPAIR OF DNA.
THE SAME STUDY AS THAT DESCRIBED ABOVE WILL BE CARRIED OUT ON HUMANS SUFFERING FROM SUCH DIFFERENT COMPLAINTS AS ATAXIA TELANGIECTASIA, BLOOM'S SYNDROME, FANCONI'S ANAEMIA, XERODERMA PIGMENTOSUM, RETINOBLASTOMA, COCKAINE'SYNDROME...IN ORDER TO ESTIMATE THE RATE AND POSSIBLE SPECIFIC NATURE OF CHROMOSOMAL BREAKAGE IN THEIR LYMPHOCYTES.
IN THESE DISEASES WHERE MALIGNANCIES OFTEN OCCUR, ABNORMAL CLONES WILL BE STUDIED AND TUMORS ANALYSED.