Nail Patella Syndrome

1. Nail Patella Syndrome By Emily Aldridge NS215G Mendelian and Human Genetics

2. Nail Patella Syndrome (NPS) Overview Also Known as Fong Disease and Turner-Kieser Syndrome. Hereditary disorder Known as an inherited disorder for over 100 years. Affects the nails, skeletal system, and kidneys. 1/50,000 people Affects males and females equally. Occurs in all ethnic groups Strongest risk for NPS is a family history.

3. The Cause of NPS • Mutated gene LIM Homebox Transcription Factor 1-Beta (LMX1B). • Located on the long arm of chromosome 9 • Codes for a protein that is important in organizing embryonic limb development. • Inherited in an autosomal dominant manner. • Possession on only 1 copy of the defected gene is enough to cause disease. • Child has 50/50 chance to inherit the disease-causing mutation.

4. NPS Symptoms • Medical signs vary widely between patients. • Some don’t display symptoms. • Discovered to have NPS only when genetic studies trace their family history. • Scientist doing studies to find out why some people display symptoms and others don’t.

5. Nails Thumbnail affected by NPS • Found in 80 % of NPS Patients • One or more fingers but rarely all. • Affects mostly thumb and index finger nails. • May be small and concave with pitting, ridges, splits, and/or discoloration. • Lunula are sometimes triangular. • Toenails are less often affected.

6. Knee Caps NPS Kneecap • One or both may be missing or poorly developed. • If present likely to dislocate. • Knees have a square appearance. • Beside the knee cap, other support structures such as bones, ligaments, and tendons maybe malformed. • Since these stabilized the knee cap, can cause it to be painful or difficult to walk.

7. Hip Bones • 80 % of patients have bony projections called posterior iliac horns. • Internal/not obvious unless detected on x-ray. • Not associated with any other disease.

8. Kidney Disease • Incidence of Kidney Disease in NPS patients is approximately 30-50% • More apparent later in life. • Should have regular urinalysis to monitor changes in kidney function.

9. Feet and Ankles Many are born with a club foot deformities due to misplacement of tendons around the foot and ankle.

10. Detection • Diagnosis is often made on visual medical clues such as the abnormalities of nails and kneecaps. • Confirmed by x-rays of the affected bones. • Prenatal Diagnosis (as of 2001)is not yet widely available. • Genetic Testing is available as of early 2001 • Only through research institutes that are working to further characterize this disorder. • Can’t predict which signs will develop and the severity of the symptoms. • Improved genetic tests are anticipated in the future.

11. Treatment • Not usually necessary • Kidney treated with dialysis or transplant. • New kidney won’t be affected. • If walking becomes too painful the patient will have to resort to a wheelchair. • Orthopedic surgery may be necessary for congenital (a condition present at birth)clubfoot. • Manipulation or surgery to correct hip dislocation. • Should be screened for scoliosis.

12. Many people who have Nail Patella Syndrome go on to live a normal and healthy life.

13. Bibliography • Club Foot Picture. CDC Public Health Image Library. • Dunston, Jennifer A., Tyler Reimschisel, Yu-Qiang Ding, Elizabeth Sweeney, Randy L. Johnson, Zhou-Feng Chen, and Iain McIntosh. "A neurological phenotype in nail patella syndrome (NPS) patients illuminated by studies of murine Lmx1b expression." European Journal of Human Genetics 13 (2005): 330-35. • Lohr, John T. "Nail-Patella Syndrome." HealthAtoZ. 14 Aug. 2006. 26 July 2008 <http://http://www.healthatoz.com/healthatoz/atoz/common/standard/transform.jsp?requ esturi requestURI=/healthatoz/Atoz/ency/nail-patella_syndrome.jsp • Mansour, Joanne, ed. "What is NPS." Nail Patella Syndrome Worldwide. 26 July 2008 <http://www.nailpatella.org>. • Nail Patella Syndrome. Journal of Medical Genetics. • Wijten, Jan. Nail Patella Syndrome. 6 Dec. 2006.