Chromosome xxy does not have a family genetic problem, it is a mismatch of chromosomes before childbirth. Under normal circumstances, there are 46 chromosomes in the human body cells, half from the father and half from the mother, the male sex chromosomes are X and Y. If xxy occurs, it means that the sex chromosomes have an extra X chromosome, which is related to the fact that the X chromosome did not separate when the male spermatozoa were meiotic, which belongs to the chromosomes appearing to be mismatched, and it is not a family genetic problem. Chromosome xxy will cause the fetus to have Kernicterus syndrome, the fetus is born with lower body weight, small head circumference, smaller penis and testicles, and also prone to some congenital malformations, such as finger curvature and hypospadias, and after puberty it will show small testicles, azoospermia, and taller stature, longer limbs, and in some patients, there will also be breast development and reduced bone density. Crohn’s syndrome is a chromosomal abnormality disorder, and prenatal genetic diagnosis is recommended to minimize the birth of affected children.