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Prenatal Genetic Diagnosis

Conventional prenatal chromosome testing (QF-PCR, G-Banding)

Chromosomal abnormalities are changes (mutations) in large parts of DNA, the chromosomes. The most frequent chromosomal abnormality is the Down’s Syndrome in which the presence of one additional copy of chromosome 21 (Trisomy 21) is observed.

Most chromosomal abnormalities are diagnosed by the “conventional” karyotype, which is the standard examination of all chromosomes in prenatal testing of fetal cells from a sample of amniotic fluid or chorionic villi.

The conventional karyotype depicts the characteristic number and morpohology of the chromosomes, in order to detect all the chromosomal abnormalities that are visible under the microscope. Results are produced within 15 to 20 and therefore is preceded by rapid QF-PCR diagnosis of Down syndrome and other most common abnormalities within 24 – 48 hours of sampling.

Molecular karyotype (aCGH)

Molecular Karyotype is a new method that is increasingly applied in the prenatal diagnosis of chromosomal abnormalities, as it provides the ability to analyze chromosomes at a much higher level than the conventional karyotype and detects mutations much smaller than those visible under a microscope.

The molecular karyotype allows the detection of abnormalities involving all chromosomes (eg trisomy 21, etc.) as well as small deficiencies and duplications that may be associated with severe clinical manifestations and known syndromes such as DiGeorge, Prader Willi syndrome, Angelman and many more, where they cannot be detected with the conventional karyotype.

The application of the molecular karyotype to prenatal testing can lead to the additional detection of clinically significant findings in a percentage of up to ~ 8% in high-risk pregnancies and a significant percentage in low-risk pregnancies compared to the conventional karyotype.

COMPLETE CYTOVIEW 512

Complete Cytoview is a specially designed chromosome analysis system with a molecular karyotype, based on instructions from the International Consortium of Cytogenetics (ISCA), which examines in great detail and with diagnostic accuracy all human DNA and specially related areas, according to a recent bibliography, with 512 genetic diseases and which are analyzed with a very high level of clarity.

In addition, the most frequent mutations of two of the most common genetic diseases, Cystic Fibrosis and Spinal Muscular Atrophy, are screened. A first result for Down syndrome and the most common syndromes is available in 24 hours and the full analysis in 5 to 7 working days.

Diagnosis of genetic diseases and syndromes in prenatal cases

Technological developments in molecular genetics have allowed us today the use of rapid methods for the reliable detection of any known mutations that lead to the development of genetic syndromes and diseases such as Thalassemia, cystic fibrosis, neuromuscular diseases etc. Access To Genome laboratories ensure the reliable application of these methods to enable the diagnosis of even very rare genetic diseases in cases with a family history or other relevant evidence.

Molecular testing of congenital infections in prenatal testing

The use of molecular biology methods such as polymerase chain reaction (PCR) may allow the detection of the genetic material (DNA / RNA) of microorganisms and viruses such as coronavirus, cytomegalovirus, toxoplasma, etc. with high analytical sensitivity and specificity in a sample of amniotic fluid during prenatal testing. The test is performed in cases where there are indications after a relevant antibody test.