Example of Trisomy 21 detected via quantitative PCR short tandem repeat assay Germline<unk>  is typically detected through karyotyping, a process in which a sample of cells is fixed and stained to create the typical light and dark chromosomal banding pattern and a picture of the chromosomes is analyzed. Other techniques include fluorescence in situ hybridization (FISH), quantitative PCR of short tandem repeats, quantitative fluorescence PCR (QF-PCR), quantitative PCR dosage analysis, Quantitative Mass Spectrometry of Single Nucleotide Polymorphisms, and comparative genomic hybridization (CGH). These tests can also be performed prenatally to detect<unk>  in a pregnancy, through either amniocentesis or chorionic villus sampling. Pregnant women of 35 years or older are offered prenatal testing because the chance of chromosomal<unk>  increases as the mother's age increases. Recent advances have allowed for less invasive testing methods based on the presence of fetal genetic material in maternal blood. See Triple test and Cell-free fetal DNA. Types +key color significance lethal normal male phenotype Klinefelter syndrome (abnormal male) polysomy X and/or Y (abnormal male) normal female phenotype Turner's syndrome (abnormal female) polysomy X (abnormal female) + Non-autosomal 0 X XX XXX XXXX XXXXX 0 0 X XX XXX XXXX XXXXX Y Y XY XXY XXXY XXXXY XXXXXY YY YY XYY XXYY XXXYY XXXXYY XXXXXYY YYY YYY XYYY XXYYY XXXYYY XXXXYYY XXXXXYYY YYYY YYYY XYYYY XXYYYY XXXYYYY XXXXYYYY XXXXXYYYY YYYYY YYYYY XYYYYY XXYYYYY XXXYYYYY XXXXYYYYY XXXXXYYYYY +key color significance case where complete non-mosaic trisomy can never survive to term case where complete non-mosaic trisomy can rarely (barring other complications) survive to term case where complete non-mosaic trisomy can frequently (barring other complications) survive to term +Autosomal # monosomy trisomy 1 1p36 deletion syndrome1q21.1 deletion syndrome Trisomy 1 2 2q37 deletion syndrome Trisomy 2 3 Trisomy 3 4 Wolf–Hirschhorn syndrome Trisomy 4 5 Cri du chat5q deletion syndrome Trisomy 5 6 Trisomy 6 7 Williams syndrome Trisomy 7 8 Monosomy 8pMonosomy 8q Trisomy 8 9 Alfi's syndromeKleefstra syndrome Trisomy 9 10 Monosomy 10pMonosomy 10q Trisomy 10 11 Jacobsen syndrome Trisomy 11 12 Trisomy 12 13 Patau syndrome 14 Trisomy 14 15 Angelman syndromePrader–Willi syndrome Trisomy 15 16 Trisomy 16 17 Miller–Dieker syndromeSmith–Magenis syndrome Trisomy 17 18 Distal 18q-Proximal 18q- Edwards syndrome 19 Trisomy 19 20 Trisomy 20 21 Down syndrome 22 DiGeorge syndromePhelan–McDermid syndrome22q11.2 distal deletion syndrome Cat eye syndromeTrisomy 22
Aneuploidy
Germline mosaicism
Polyploidy
Defocus aberration
Germline mutation
Robertsonian translocation
Chromosomal translocation
Heteroxeny