Karyotype

This is a photo of the chromosomes from the amniocentesis test. You can click on the image to make it bigger. There are 46 chromosomes in each cell of the human body. One is inherited from the mother, and the other, from the father. It's what gives us our genetic diversity! Note the dark bands in each chromosome, these are DNA tightly compressed. Different organisms have different numbers of chromosomes. Primates have 48, the hare has 46, and the potato has 48 as well!

With the karyotype ( A photomicrograph of chromosomes arranged according to a standard classification), the lab figures out which chromosomes are which and lines them up. In Down's Syndrome, you would see three number 21 chromosomes and in Trimsomy 18, you would see 3 number 18 chromosomes. Luckily, none of this existed in our baby, thank goodness! The neat thing to look for is how many chromosomes under X and Y. The baby has two X chromosomes and that is how they know it is a girl!