Down syndrome, named after Dr. J. Langdon Down after reporting the first case in 1866, is a chromosomal condition, related to chromosome 21, that occurs in one in every 800 to 1,000 live births. National Down Syndrome Awareness Month, celebrated in October, aims to educate and make aware to the community the risks, symptoms and treatments for Down syndrome (also known as Trisomy 21). According to the National Down Syndrome Society, in America there are approximately 350,000 people with Down syndrome.
What Increases Your Risk?
Being an older mother. Women over age 35 have an increased risk for having a child with Down syndrome; as women age, that risk increases. Being an older father. Men ages 45 and up may have a slightly increased risk for having a child with Down syndrome. It is not as significant, however, as the mother's age. Having had a child with Down syndrome. Those who have already had a child with Down syndrome have a 1-in-100 chance of having another child with the condition.
What Are the Signs?
Typically, a child presents signs of Down syndrome at birth or shortly afterward. Some common characteristics among them are:
Flat facial profile 90% Poor Moro reflex 85% Hypotonia (low muscle tone) 80% Hyperflexibility of large joints 80& Loose skin on back of neck 80% Slanted upper and lower eyelids (the almond shaped eyes) 80% Dysmorphic pelvis on radiographs 70% Small round ears 60% Hypoplasia of small finger, middle phalanx (curvature of pinkie and middle finger)60% Single palmar crease 45% Brushfield spots 87% Gap between big toe and first toe >64%
Those with Down syndrome oftentimes have medical and developmental disorders as well, including:
Mental retardation >95% Growth retardation >95% Early Alzheimer's disease Affects 75% by age 60% Congenital heart defects (atrioventricular canal defect, ventricular septal defect, atrial septal defect, patent ductus arteriosus, tetralogy of Fallot) 40% Hearing loss (related to otitis media with effusion or sensorineural) 40 to 75% Ophthalmic disorders (congenital cataracts, glaucoma, strabismus) 60% Epilepsy 5 to 10% Gastrointestinal malformations (duodenal atresia, Hirschsprung disease) 5% Hypothyroidism 5% Leukemia 1% Atlantoaxial instability <1% Increased susceptibility to infection (pneumonia, otitis media, sinusitis, pharyngitis, periodontal disease) Unknown Infertility >99% in men; anovulation in 30% of women
Although Down syndrome is a life-long condition with no significant treatment, many people with Down syndrome live well-balanced, happy lives well into their 50s
There are three types of Down Syndrome. It is estimated that ninety-five percent of the individuals born with Down Syndrome have Trisomy 21. What this means is the individuals have an extra twenty-first chromosome. No known cause has been discovered but research says that the extra chromosome could have resulted from some genetic material sticking together. All of the chromosomes are normal but the extra twenty-first causes a genetic imbalance that alters the normal course of development.
About three percent of the individuals born with Down Syndrome have Translocation, the only type that can result from a condition in the parent's genes. Only two percent have the least common form of Down Syndrome called Mosaic, where a faculty cell division occurs after fertilization.