ABSTRACT
Twenty-eight laboratories evaluated a new fluorescence in situ hybridization (FISH) strategy for chronic myeloid leukemia. In a three-part study, bcr/abl1 D-FISH probes were used to study bone marrow specimens. First, laboratories familiarized themselves with the strategy by applying it to known normal and abnormal specimens. Then, collectively the laboratories studied 20 normal and 20 abnormal specimens blindly and measured workload. Finally, each laboratory and two experts studied six serial dilutions with 98-0% abnormal nuclei. Using the reported normal cutoff of < 1% abnormal nuclei, participants reported no false-negative cases and 15 false-positive cases (1-6.6% abnormal nuclei). Results provided by participants for serial dilutions approximated the expected percentages of abnormal nuclei, but those from the experts exhibited greater precision. The clinical sensitivity, precision, nomenclature, workload, recommendations for training, and quality assurance in methods using D-FISH in clinical practice are discussed.
Subject(s)
Clinical Laboratory Techniques/standards , Fusion Proteins, bcr-abl/genetics , In Situ Hybridization, Fluorescence , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Bone Marrow/pathology , Fluorescent Dyes , Humans , In Situ Hybridization, Fluorescence/instrumentation , In Situ Hybridization, Fluorescence/methods , In Situ Hybridization, Fluorescence/standards , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Quality Control , Sensitivity and Specificity , WorkloadABSTRACT
Phenotypic analysis has been practised in many different ways, the most common being the recognition of normal and abnormal physical and biochemical characteristics and their patterns of inheritance. As different tools became available to analyze the characteristics of individuals the study of the phenotype and consequently of the genotype became more sophisticated. By the mid 1970's ultrasonography became a major tool in the analysis of human disease, and more recently it has contributed to the analysis of the human fetal phenotype in utero. This method, when used in conjunction with cytogenetic and biochemical analysis of the amniotic fluid, constitutes the main thrust of genetic prenatal diagnosis today. This paper describes and proposes the systematic use of ultrasonography, in conjunction with biochemical and cytogenetic tests to examine pregnancies at risk of congenital and inherited diseases and those that show signs of abnormality. We have examined 1500 fetuses and have detected conditions that affect only one system, like the skeletal dysplasias (osteogenesis imperfecta, thanatophoric dysplasia, diastrophic dwarfism, achondrogenesis I, Jeune syndrome and many others), neural tube defects, gastroschisis, multiple congenital malformations syndromes (Vater, Vacterl, Weyers olygodactyly, Meckel syndrome, and others). The analysis of the functionality of the fetus is one of the major achievements of genetic prenatal diagnosis by ultrasonography.
