A karyotype test is a type of genetic testing. It looks at the size, shape, and number of chromosomes in a sample of cells from your body. Chromosomes are found in the cell nucleus, which is like the command center of a cell. Chromosomes contain your genes. Genes carry information, called DNA, that controls what you look like and how your body works.You inherit your chromosomes from your parents. Normally, all your cells (except for egg and sperm cells) have a set of the same 46 chromosomes. The chromosomes are grouped into 23 pairs. Each pair has two chromosomes, one coming from each parent. You may develop certain genetic disorders if your cells:

• Are missing whole chromosomes or pieces of chromosomes
• Have extra chromosomes or extra pieces of chromosomes

Quantitative Fluorescence PCR (QF-PCR) is a molecular-based technique employed for prenatal and postnatal diagnosis of rapid aneuploidy detection(RAD) of chromosomes 13, 18, 21, X, and Y.A technique based on the amplification of chromosome-specific DNA sequences (STR, short tandem repeats) polymorphic in length, is used to determine the presence of different alleles. Employing fluorescent primers, the amplified segments can be visualized and quantified as peak areas on automated DNA scanners. QF-PCR is rapid, cost-effective, almost entirely automated, small sample size with high accuracy, and can detect most abnormalities diagnosed by conventional karyotyping.

Karyotyping

• Abnormal fetal ultrasound and presenceof soft markers like hypoplastic nasalbone, Increased NT, Echogenic bowel etc.
• Maternal serum screening positive forchromosome aneuploidies
• NIPT positive for chromosomeaneuploidies
• Parental chromosomal rearrangement ormosaicism
• Previous history of recurrent miscarriages
• Previous fetus/baby with chromosomalabnormality

QFPCR

• Abnormal fetal ultrasound and presenceof soft markers like hypoplastic nasalbone, Increased NT, Echogenic bowel etc.
• Maternal serum screening positive forchromosome aneuploidies
• NIPT positive for chromosomeaneuploidies
• Parental chromosomal rearrangement ormosaicism
• Previous history of recurrent miscarriages
• Previous fetus/baby with chromosomalabnormality

Karyoytyping

A karyotype test looks for unusual changes in chromosomes. It may be used to:

• Check an unborn baby for chromosome problems
• Check you and/or your family members for specific chromosome problems if you:
• Have a genetic disorder that runs in your family
• Have symptoms that may be from a genetic disorder
• Find out if abnormal chromosomes are causing problems having children, including:
• Male or female infertility
• Miscarriages, if you have lost two or more pregnancies before 20 weeks
• Stillbirth
• Help diagnose and/or make treatment decisions for certain types of cancer and blood disorders

FISH

• Screening result suggests aneuploidy
• Advanced maternal age
• One major or at least two minor fetal structural defects found on ultrasound
• Previous fetus or child with aneuploidy
• Parent of this pregnancy has a structural chromosome abnormality (e.g.,translocation, inversion) involving chromosome 21, 13, 18, X, or Y
• Parent of this pregnancy has an extra chromosome (e.g., Down syndrome, XXX syndrome, Klinefelter syndrome)

Karyotyping - Chromosomal Analysis / Light Microscopy

QF PCR analysis includes amplification, detection and analysis of chromosome-specific DNA sequences known as genetic markers or small tandem repeats (STRs).