Periventricular heterotopia is a condition in which nerve cells (neurons) do not migrate properly during the early development of the fetal brain, from about the 6th week to the 24th week of pregnancy. Heterotopia means "out of place." In normal brai READ MORE

Permanent neonatal diabetes mellitus is a type of diabetes that typically appears within the first 6 months after birth (the neonatal period) and continues throughout life. Diabetes is characterized by high levels of glucose in the blood, also called READ MORE

Peroxisomal acyl-CoA oxidase deficiency is a disorder that causes deterioration of nervous system functions (neurodegeneration) beginning in infancy. Newborns with peroxisomal acyl-CoA oxidase deficiency have weak muscle tone (hypotonia) and seizures READ MORE

Perrault syndrome is a rare condition that causes different patterns of signs and symptoms in affected males and females. A key feature of this condition is hearing loss, which occurs in both males and females. Affected females also have abnormalitie READ MORE

Perry syndrome is a progressive brain disease that is characterized by four major features: a pattern of movement abnormalities known as parkinsonism, psychiatric changes, weight loss, and abnormally slow breathing (hypoventilation). These signs and READ MORE

Persistent Müllerian duct syndrome is a disorder of sexual development that affects males. Males with this disorder have normal male reproductive organs, though they also have a uterus and fallopian tubes, which are female reproductive organs. The ut READ MORE

Peters anomaly is characterized by eye problems that occur in an area at the front part of the eye known as the anterior segment. The anterior segment consists of structures including the lens, the colored part (iris) of the eye, and the clear coveri READ MORE

Peters plus syndrome is an inherited condition that is characterized by eye abnormalities, short stature, an opening in the lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate), distinctive facial features, and intellect READ MORE

Peutz-Jeghers syndrome is characterized by the development of noncancerous growths called hamartomatous polyps in the gastrointestinal tract (particularly the stomach and intestines) and a greatly increased risk of developing certain types of cancer. READ MORE

Pfeiffer syndrome is a genetic disorder characterized by the premature fusion of certain skull bones (craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape of the head and face. Pfeiffer syndrome also aff READ MORE

PGM3 -congenital disorder of glycosylation ( PGM3 -CDG) is an inherited condition that primarily affects the immune system but can also involve other areas of the body. The pattern and severity of this disorder's signs and symptoms typically vary. Mo READ MORE

Phenylketonuria (commonly known as PKU) is an inherited disorder that increases the levels of a substance called phenylalanine in the blood. Phenylalanine is a protein building block (an amino acid) that is obtained from eating certain foods (such as READ MORE