2024年11月14日 · Prader-Willi syndrome occurs because certain paternal genes that should be expressed aren't because: Paternal genes on chromosome 15 are missing. The child inherited two copies of chromosome 15 from the mother and no chromosome 15 from the father. There's some change in paternal genes on chromosome 15.

2024年3月8日 · Rarely, Angelman syndrome is caused when two paternal copies of the gene are passed down instead of one from each parent. Risk factors. Angelman syndrome is rare. Researchers often don't know what causes the genetic changes that result in the disease. Most people with Angelman syndrome don't have a family history.

2024年10月29日 · Causes. Klinefelter syndrome occurs because of a random change in the egg or the sperm that causes a baby assigned male at birth to be born with an extra X sex chromosome.

2022年2月11日 · Before birth. Turner syndrome may be suspected prenatally based on prenatal cell-free DNA screening — a method to screen for certain chromosomal abnormalities in a developing baby using a blood sample from the mother — or prenatal ultrasound.

2023年5月25日 · Overview. Noonan syndrome is a genetic condition that stops typical development in various parts of the body. It can affect a person in several ways, including unusual facial features, short height, heart problems and other physical problems.

2024年11月12日 · Symptoms. Each person with Down syndrome is an individual. Problems with intellect and development are usually mild to moderate.

2025年1月15日 · Triple X syndrome, also called trisomy X or 47,XXX, is a genetic disorder that affects about 1 in 1,000 females.

2022年11月24日 · Postpartum depression in fathers — sometimes called paternal postpartum depression — can have the same negative effect on partner relationships and child development as postpartum depression in mothers can.

2018年1月6日 · Autism spectrum disorder includes conditions that were previously considered separate — autism, Asperger's syndrome, childhood disintegrative disorder and an unspecified form of pervasive developmental disorder.

2022年12月22日 · Preventing infections. Children with sickle cell anemia might receive penicillin from about 2 months old to 5 years old, or longer.