KARYOTYPING, IDENTIFICATION OF CHROMOSOMAL ABNORMALITIES

MAY-JUNE 1997

Dr. A.L. MUDALIAR POST GRADUATE INSTITUTE OF BASIC MEDICAL SCIENCES , CHENNAI

GUIDE: Dr. P.M. GOPINATH

SUMMER RESEARCH AS AN UNDERGRADUATE

The work involved short term (69-72h) whole blood culture of human peripheral blood lymphocytes by using the lectin phytohemagglutinin for stimulating their proliferation. Cell growth was arrested at metaphase with colchicine and cell density and chromosome spread were examined after slide preparation. Metaphase chromosomes were stained and studied using: G banding with trypsin using Giemsa to differentiate the chromosomes based on the light and dark stained regions along the length of the chromosome C banding using Barium hydroxide and Giemsa to study selective staining of constitutive heterochromatin (in proximal long arm of 1, 9, 11 and distal arm of Y chromosome) Silver impregnation to differentially stain Nucleolar Organizer regions (in short arms of Chromosomes 13, 14, 15, 21, 22) Karyotyping of my blood sample was done and no abnormalities were detected. Karyotyping was also done for a patient with congenital heart disease-ventricular septal defect and primary amenorrhoea. She was found to have a 47,XXX karyotype.I also did karyotyping for a child after observing it for some days. The karyotype indicated trisomy 21.