One of the most common disabilities associated with developmental delay is Down syndrome. This is a genetic condition that is seen throughout our society today and is still undergoing intensive investigation. Although Down syndrome has been alluded to through time, it was first accurately described by English physician, John Langdon Down in the late 19th century, and identified as a chromosomal anomaly by French physician, Jerome Lejeune, in 1959 (National Down Syndrome Society (NDSS), 1995-2003). An extra chromosome 21 characterizes Down syndrome. This extra chromosome impacts almost every organ system of the body. "This results in a wide spectrum of consequences, some of which are life threatening, some of which significantly alter the individual's life course, and some of which are merely curious characteristics found more often among individuals with Down syndrome" (Qtd. in Spiker and Hopmann, 1997). .
Common characteristics associated with Down syndrome include cardiac complications, large tongue, low muscle tone, impaired hearing, vision problems, abnormal ear shape, large gap between first and second toes, and developmental delay. The life expectancy of a person diagnosed with Down syndrome has significantly increased due to medical and surgical advances in cardiac and respiratory conditions. Currently, the mortality rate falls between 40 and 60 years of age, which is a significant increase from 9 years of age. However, it still exceeds that of the general population (Yang, Rasmussen, Friedman, 2002). In today's society, it is becoming more accepted to have a disability than it has been in years past. This is largely due to the encouragement to the family to care for those born with Down syndrome versus the institutionalized care that was predominantly used prior to 1970 (Van Riper and Cohen, 2001). .
Uniform education is dying out and alternative methods are being implemented to help those with developmental delay acquire knowledge and skills based on their personal handicaps.