Answer from: Douglas Lester, PhD, MSc, BSc (Hons)
Karyotyping looks at the number, size, and structure of all your human chromosomes. It can pick up approximately 5% of all human mutations, but only if they involve millions of deleted, duplicated, or inverted letters. For example, just recently, they found a common inversion of 1.6 million letters. The letters are being completely inverted, and this is on the male-specific Y chromosome. It’s finding as many as one in five males in Eastern European ancestry. If you’ve got this inversion, such males are eight times more likely to suffer sperm-specific infertility problems; the male lacks this inversion. This is only a recent finding. Karyotyping can also pick up either complete chromosome duplication. For example, Kleinfelder Syndrome causes infertility in males due to an extra X chromosome being present. So normal males have got 1 X and a Y; with Kleinfelder, they’ve got 2 X chromosomes and a Y.
Karyotyping - what is it and when do I need it?
Have you been diagnosed with infertility? Perhaps your fertility doctor is planning to run various tests? Learn more about tests and laboratory procedures that allow your doctor to examine your set of chromosomes. If there is any suspicion that there are any abnormalities or structural problems within your or your partner’s chromosomes, karyotyping might be for you.