Peters plus syndrome

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

The eye problems seen in Peters plus syndrome occur in an area at the front part of the eye known as the anterior chamber. The anterior chamber is the fluid-filled space between the clear covering of the eye (cornea) and the colored part of the eye (iris). An eye problem called Peters anomaly is the most common anterior chamber abnormality seen in Peters plus syndrome. Peters anomaly involves thinning and clouding of the cornea and attachment of the iris to the cornea, which causes blurred vision. It may also be associated with clouding of the lens of the eye (cataracts) or other lens abnormalities. The severity of eye symptoms can vary between individuals with Peters plus syndrome, even among members of the same family.

Peters plus syndrome is characterized by Peters anomaly plus other typical signs and symptoms. All people with Peters plus syndrome have short stature. Individuals with this condition are typically shorter than average at birth. The height of adult males with this condition ranges from 141 centimeters to 155 centimeters (4 feet, 7 inches to 5 feet, 1 inch), and the height of adult females ranges from 128 centimeters to 151 centimeters (4 feet, 2 inches to 4 feet, 11 inches). Individuals with Peters plus syndrome also have shortened upper limbs (rhizomelia) and shortened fingers and toes (brachydactyly).

Developmental delay is present in most children with Peters plus syndrome. The extent of intellectual disability typically ranges from mild to severe, although some individuals have normal intelligence. The severity of physical features does not predict the level of developmental delay.

The characteristic facial features of Peters plus syndrome include a prominent forehead, narrow eyes, a long area between the nose and mouth (philtrum), a pronounced double curve of the upper lip (Cupid's bow), and a broad neck. A cleft lip with or without a cleft palate is present in about half of people with this condition.

Less common signs and symptoms of Peters plus syndrome include heart defects, structural brain abnormalities, hearing loss, reduced thyroid activity (hypothyroidism), and kidney or genital abnormalities.

Peters plus syndrome is a rare genetic disorder; its incidence is unknown. Fewer than 70 people with this condition have been reported worldwide.

Mutations in the B3GALTL gene cause Peters plus syndrome. The B3GALTL gene provides instructions for making an enzyme called beta-1,3-glucosyltransferase (B3Glc-T), which is involved in the complex process of adding sugar molecules to proteins (glycosylation). Glycosylation allows proteins to perform a wider variety of functions. Most mutations in the B3GALTL gene lead to the production of an abnormally short, nonfunctional version of the B3Glc-T enzyme, which disrupts glycosylation. It is unclear how the loss of functional B3Glc-T enzyme leads to the signs and symptoms of Peters plus syndrome.

Read more about the B3GALTL gene.

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.