Sensorineural-associated hearing impairment and hoarseness was also observed in a 10-year-old girl and her father, and in a number of other cases.Other characteristics seen with the syndrome include developmental delay, growth retardation, pulmonary stenosis (an obstruction of blood-flow from the right ventricle of the heart to the pulmonary artery) with associated dyspnea (shortness of breath), and renal agenesis (failure of the kidneys to develop during the fetal period). Undescended testes, hyperactivity and aggressive behavior have also been noted. Genetics
Nasodigitoacoustic syndrome is thought to be caused by a mutation in a gene on the X chromosome. A 2007 study concluded, based on analysis of microsatellite markers (small gene sequences found in common among individuals having the same ethnicity, ancestry or genetic disease) of the family described by Keipert, that this gene was likely located on the long arm of the X chromosome between positions Xq22.2–q28. This is not definitive, however, and no specific gene has been named.The syndrome is strongly believed to be inherited in an X-linked recessive manner. When a female carries a mutated gene on one of her two copies of the X chromosome, there is a 50% chance of passing the mutation on to her children. Much like her, a daughter inheriting this mutation will be a carrier, but will not herself have the associated disease. However, a son who inherits the mutation will have the disease; this is because males have only one copy of the X chromosome and therefore could only express the disease mutation.
Treatments, depending upon the cause and severity, may include a pharmacological approach (i.e., the use of certain steroids), or surgical intervention, like a cochlear implant.Pulmonary, or pulmonic stenosis is an often congenital narrowing of the pulmonary valve; it can be present in nasodigitoacoustic-affected infants. Treatment of this cardiac abnormality can require surgery, or non-surgical procedures like balloon valvuloplasty (widening the valve with a balloon catheter). History and epidemiology
The syndrome was initially described in 1973 by James A. Keipert and associates. They reported of two brothers with broad distal phalanges, sensorineural hearing loss, and facial features consistent with what would become known as Keipert or "nasodigitoacoustic" syndrome. Although no specific rate of incidence has been determined, the syndrome is considered a rare disease by both the Office of Rare Diseases (ORDR) at the National Institutes of Health, and Orphanet. This suggests, respectively, that nasodigitoacoustic syndrome affects less than 200,000 people in the U.S., or affects no greater than 1 per 2,000 people in Europe. References
Publications
Gorlin, R. J.; Toriello, H. V.; Cohen, M. M. (1995). Hereditary hearing loss and its syndromes. U. S.: Oxford University Press. pp. 208–209. ISBN 9780195065527. Retrieved April 21, 2011. External links

Nasodigitoacoustic syndrome listing at the Office of Rare Diseases website
Keipert syndrome - Orphanet