Puberty is the time of development from a child to an adult. This process is considered late if it has not started by age 15 (for girls) and age 17 (for boys).

Screening for Klinefelter syndrome by invasive diagnostics, requiring amniocentesis or chorionic villus sampling, carries a high risk of miscarriage and fetal malformations. NIPT fetal DNA testing in maternal blood is a new, safe diagnostic method and an effective prenatal screening option for Klinefelter syndrome.

Bloch-Sulberger syndrome is a genetic disorder that severely affects the skin, hair, teeth, and central nervous system. It is characterized by blisters on the trunk and limbs at birth. These blisters heal over time, but they leave behind hyperpigmented skin.