Chromosome 17p duplication

Alternate names

Duplication 17p; Trisomy 17p; 17p duplication; 17p trisomy; Partial trisomy 17p; Dup(17p)

Definition

Chromosome 17p duplication is a chromosome abnormality that occurs when there is an extra copy of genetic material on the short arm (p) of chromosome 17.

Cause

This condition occurs when there is an extra copy of genetic material on the short arm (p) of chromosome 17.

Inheritance

• Most cases are not inherited and occur randomly when the parents’ sperm or egg cells formed, or very shortly after the egg and sperm joined.
• In some cases, the duplication is inherited from a parent with a chromosome abnormality (who may or may not have symptoms of a chromosome abnormality).
• Whether or not the duplication was inherited from a parent, a person with the duplication can pass it on to his or her child.

Signs and symptoms

The severity of the condition and the signs and symptoms depend on the size and location of the duplication and which genes are involved. Features that often occur in people with chromosome 17p duplication include slowed growth both before and after birth; developmental delay; reduced muscle tone (hypotonia); congenital heart defects; and distinctive facial features.

Clinical presentation

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed.

80%-99% of people have these symptoms

• Clinodactyly of the 5th finger(Permanent curving of the pinkie finger)
• Global developmental delay
• Intellectual disability(Mental deficiency)
• Intrauterine growth retardation(Prenatal growth deficiency)
• Low-set ears(Low set ears)
• Microcephaly(Abnormally small skull)
• Micrognathia(Little lower jaw)
• Muscular hypotonia(Low or weak muscle tone)
• Short stature(Decreased body height)

30%-79% of people have these symptoms

• Flexion contracture(Flexed joint that cannot be straightened)
• Generalized hirsutism(Excessive hairiness over body)
• High palate(Elevated palate)
• Hydronephrosis
• [[Hypertelorism](Wide-set eyes)
• Hypertonia
• Hypoplasia of penis(Underdeveloped penis)
• Malar flattening(Zygomatic flattening)
• Narrow mouth(Small mouth)
• Polycystic kidney dysplasia
• Ptosis(Drooping upper eyelid)
• Short neck(Decreased length of neck)
• Urethral stenosis(Narrowing of the urethra)
• Urethral valve
• Wide nose(Broad nose)

5%-29% of people have these symptoms

• Aortic valve stenosis(Narrowing of aortic valve)
• Broad eyebrow(Broad eyebrows)
• Cataract(Clouding of the lens of the eye)
• Cleft palate(Cleft roof of mouth)
• Coarse facial features(Coarse facial appearance)
• Downslanted palpebral fissures(Downward slanting of the opening between the eyelids)
• Hearing impairment(Deafness)
• High anterior hairline(High frontal hairline)
• Hydrocephalus(Too much cerebrospinal fluid in the brain)
• Hypoplastic left heart(Underdeveloped left heart)
• Low posterior hairline(Low hairline at back of neck)
• Macroglossia(Abnormally large tongue)
• Patent ductus arteriosus
• Prominent metopic ridge
• Prominent nose(Big nose)
• Scoliosis
• Skeletal muscle atrophy(Muscle degeneration)
• Smooth philtrum
• Strabismus(Cross-eyed)
• Talipes
• Tapered finger(Tapered fingertips)
• Thick nasal alae
• Thick vermilion border(Full lips)
• Wide mouth(Broad mouth)

Diagnosis

Chromosome disorders may be suspected in people who have developmental delays, intellectual disabilities and/or physical abnormalities.

Several types of genetic tests can identify chromosome disorders:

• Karyotype - a karyotype is a laboratory test that produces an image of a person's chromosomes. This test can be used to diagnose large deletions.
• FISH - a laboratory technique that is used to detect and locate a specific DNA sequence on a chromosome. During FISH, a chromosome is exposed to a small DNA sequence called a probe that has a fluorescent molecule attached to it. The probe sequence binds to its corresponding sequence on the chromosome. This test can be used in combination with karyotyping for deletions that are too small to be seen on karyotype, alone. However, FISH is only useful if the person ordering the test suspects there is a deletion of a specific region of 4q.
• Array CGH - a technology that detects deletions that are too small to be seen on karyotype.
• Prenatal diagnosis is possible via amniocentesis of chorionic villus sampling.

Treatment

Treatment is based on the signs and symptoms present in each person.

NIH genetic and rare disease info

• NIH info on Chromosome 17p duplication

Chromosome 17p duplication is a rare disease.

Chromosome 17p duplication Resources
Latest articles Most recent articles Ongoing trials	Wikipedia