RESUMO
Chromosome analysing using quinacrine fluorescence was performed on 930 consecutive newborn infants. The total incidence of major chromosome aberrations including numerical changes of the sex chromosomes, and structural changes of autosomes, was 0.54%. Incidence of XYY (0.4%) and XXY (0.2%) were relatively higher as compared to other studies. About 0.75% of the newborn infants were found to have a variable bright fluorescent band located on the proximal area of the short arm (p11) rather than on the proximal long arm (q11) of chromosome No. 3. Attempts were also made to record the variable fluorescent regions on 7 autosomes and the Y chromosome.
Assuntos
Aberrações Cromossômicas , Transtornos Cromossômicos , Recém-Nascido , Aberrações Cromossômicas/epidemiologia , Inversão Cromossômica , Cromossomos Humanos 1-3 , Cromossomos Humanos 13-15 , Cromossomos Humanos 21-22 e Y , Cromossomos Humanos 4-5 , Feminino , Variação Genética , Humanos , Masculino , Ontário , Quinacrina , Cromossomos Sexuais , Coloração e Rotulagem , Translocação GenéticaRESUMO
Various factors involved in the production of "Q-bands" have been studied. It was found that a Zeiss standard WL fluorescent microscope required a shorter exposure time for photography as compared to a Zeiss photomicroscope. The minimal exposure time was obtained when the standard WL microscope was equipped with a UV light source containing a DC powered mercury burner and a concave mirror. Further, the pH and type of water used in the staining, washing and mounting of the slide were also important factors in producing clear and well differentiated "Q-bands". It also appears that the factors involved in the production of "Q-bands" effect the enhancement or quenching of fluorescence by poly d(A-T)-poly d(A-T) and salmon sperm DNA or poly dG-poly dC respectively. This preliminary report also suggests that DNA or polynucleotides with a specific base sequence may play an important role in Q-banding patterns on chromosomes.
