During the last decades, new techniques have changed the approach to the child with genetic disorders. The first step of this pathway is a correct clinical suspicion, followed by laboratory investigations aimed to confirm the diagnosis and to provide information about genotype-phenotype correlations, genetic counseling and prenatal diagnosis. In the first decade of the 20th century some intracellular structures called "chromosomes" have been identified; they are the custodians of the "Mendelian factor" and are, nowadays, named genes. In the years 1950-60, the first numerical and structural chromosome abnormalities have been identified by classic cytogenetic techniques and in particular Lejeune and collaborators demonstrated that patients with Down syndrome have three copies of chromosomes 21. Banding techniques have bettered karyotyping analysis. The innovative techniques of molecular biology have contributed to identify both those chromosomal abnormalities that cannot be detected by standard cytogenetic analysis and the cryptic rearrangements not detectable by high resolution banding, and to discover several genes. In 1992, a very innovative technique, named hybridization in situ with fluorescent (FISH) was created and allowed to localize a specific sequence of fixed chromosomes DNA samples, interphase nuclei and tissue sections.
Recent advances in the diagnostic pathway of genetic diseases
BRIUGLIA, Silvana;MESSINA, Maria Francesca;SALPIETRO DAMIANO, Carmelo
2012-01-01
Abstract
During the last decades, new techniques have changed the approach to the child with genetic disorders. The first step of this pathway is a correct clinical suspicion, followed by laboratory investigations aimed to confirm the diagnosis and to provide information about genotype-phenotype correlations, genetic counseling and prenatal diagnosis. In the first decade of the 20th century some intracellular structures called "chromosomes" have been identified; they are the custodians of the "Mendelian factor" and are, nowadays, named genes. In the years 1950-60, the first numerical and structural chromosome abnormalities have been identified by classic cytogenetic techniques and in particular Lejeune and collaborators demonstrated that patients with Down syndrome have three copies of chromosomes 21. Banding techniques have bettered karyotyping analysis. The innovative techniques of molecular biology have contributed to identify both those chromosomal abnormalities that cannot be detected by standard cytogenetic analysis and the cryptic rearrangements not detectable by high resolution banding, and to discover several genes. In 1992, a very innovative technique, named hybridization in situ with fluorescent (FISH) was created and allowed to localize a specific sequence of fixed chromosomes DNA samples, interphase nuclei and tissue sections.Pubblicazioni consigliate
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