To better understand the consequences let's consider those that affect people. As you will recall humans are 2n=46. The convention when describing a person's karyotype (chromosome composition) is to ...To better understand the consequences let's consider those that affect people. As you will recall humans are 2n=46. The convention when describing a person's karyotype (chromosome composition) is to list the total number of chromosomes, then the sex chromosomes, and then anything out of the ordinary. Most of us are 46,XX or 46,XY. What follows are some examples of chromosome number and chromosome structure abnormalities.