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PND & PGD Prenatal Diagnosis Preimplantation Diagnosis. Dr. Derakhshandeh, PhD. KARYOTYPING. genome mutations: changes in chromosome number. Technique. Karyotyping, conventional cytogenetics. Down Syndrome (Trisomy 21 (. Trisomy 2 (. Down Syndrome (Trisomy 21 (. Trisomy 18, 47 Ch.
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PND & PGD Prenatal Diagnosis Preimplantation Diagnosis Dr. Derakhshandeh, PhD
KARYOTYPING genome mutations: changes in chromosome number
Technique Karyotyping, conventional cytogenetics
Down Syndrome (Trisomy 21( Trisomy 2(
CHANGES IN CHROMOSOME STRUCTURE • Translocations • Large Deletions/Insertions • Inversions • Duplications/Amplifications
DiGeorge/Velo-Cardio-Facial/CATCH 22/Shprintzen Syndrome which is caused by a microdeletion on chromosome 22
probe for Steroid Sulfatase Deficiency which is caused by a microdeletion on the X chromosome. The "Xp22.3" probe signal is located at the Steroid Sulfatase region at Xp22.3. Since there are two X chromosomes and only one has the Steroid Sulfatase gene signal.
Interphase FISH Examples 18 (aqua), X (green), and Y (red). 13 (green), and 21 (red)
female fetus with trisomy-21 • chromosomes 18 (aqua), X (green), and Y (red). • chromosomes 13 (green), and 21 (red)
Detection of trisomy 21 by HGQ-PCRLanes 1–16 Serial dilutions for a normal individual and aDown’s syndrome patient HGQPCR (quantitative fluorescece)
PND & PGD .b-Thalassemia/ a-Thalassemia • Haemophilia (A / B) • HbD, G, E, S • DMD/BMD • SMA(I-III) • CF; Fragile X, MD, HD, charct-Mari-Tooth
PGD • Translocation • Inversion • Deletion • At least 2 independent blastromers/embryo
A limiting Factor in PGD • Chromosome abnormalities • # 70-100 % • Reduce the success of PGD
Rules and legislation of PGD • HLA typing • A child as suitable donor to an already existing child • Social sexing • …