3. A short history and some basic info
Phsical charecteristics
Health complications
Genetics
The insedence
Risk factors for DS
Prognosis for DS
Treatments for DS
Cafe down at Ankara
4. John Langdon Down
Down syndrome, Down's syndrome, or trisomy 21
is a chromosomal disorder caused by the presence of
all or part of an extra 21st chromosome. It is named
after John Langdon Down, the British doctor who
described the syndrome in 1866.
5. The disorder was
identified as a
chromosome 21
trisomy by
Jérôme
Lejeune in
1959.
6. The condition is characterized by a
combination of major and minor
differences in structure. Often Down
syndrome is associated with some
impairment of cognitive ability and
physical growth as well as facial
appearance.
7. Down syndrome
in a baby can be
identified with
amniocentesis
during
pregnancy or at
birth.
8. Individuals with Down syndrome tend
to have a lower than average cognitive
ability, often ranging from mild to
moderate developmental disabilities.
9. A small number have severe to
profound mental disability. The
incidence of Down syndrome is
estimated at 1 per 800 to 1,000
births, although these statistics are
heavily influenced by the age of the
mother.
11. Physical characteristics
single transverse palmar crease
upslanting palpebral fissures
poor muscle tone
protruding tongue
a larger than normal space between the
big and second toes
12.
13. Health complications
Congenital heart defects
Leukemia
Gastrointestinal problems
Abnormal immune system
Eye disorders, hearing loss
Obstructive sleep apnea
Early Dementia
22. a larger than
normal space
between the big
and second toes
23. Genetics
Trisomy 21
Mosaicism
Robertsonian translocation
Duplication of a portion of
chromosome 21
24. Down syndrome is a chromosomal
abnormality characterized by the
presence of an extra copy of genetic
material on the 21st
chromosome, either in whole (trisomy
21) or part (such as due to
translocations
25.
26. The effects of the extra copy vary
greatly among people, depending on
the extent of the extra copy, genetic
history, and pure chance.
Down syndrome occurs in all human
populations, and analogous effects
have been found in other species such
as chimpanzees and mice
27.
28. The extra chromosomal material can
come about in several distinct ways. A
typical human karyotype is designated
as 46,XX or 46,XY, indicating 46
chromosomes with an XX arrangement
typical of females and 46 chromosomes
with an XY arrangement typical of
males
34. Trisomy 21 is the cause of
approximately 95% of observed
Down syndromes, with 88%
coming from nondisjunction in the
maternal gamete and 8% coming
from nondisjunction in the
paternal gamete
35. Mosaicism
Trisomy 21 is usually caused by
nondisjunction in the gametes prior to
conception, and all cells in the body are
affected. However, when some of the
cells in the body are normal and other
cells have trisomy 21, it is called mosaic
Down syndrome (46,XX/47,XX,+21).
36. This can occur in one of two ways: a
nondisjunction event during an early cell
division in a normal embryo leads to a
fraction of the cells with trisomy 21; or a
Down syndrome embryo undergoes
nondisjunction and some of the cells in
the embryo revert to the normal
chromosomal arrangement.
37. • There is considerable
variability in the
fraction of trisomy
21, both as a whole
and among tissues
38. This is the cause of 1–
2% of the observed
Down syndromes.
39. Robertsonian translocation
The extra chromosome 21 material that causes
Down syndrome may be due to a
Robertsonian translocation in the karyotype
of one of the parents. In this case, the long
arm of chromosome 21 is attached to another
chromosome, often chromosome 14
(45,XX, t(14;21q)) or itself (called an
isochromosome, 45,XX, t(21q;21q))
40. Duplication of a portion of
chromosome 21
Rarely, a region of chromosome 21 will
undergo a duplication event
This will lead to extra copies of some,
but not all, of the genes on
chromosome 21 (46,XX, dup(21q)).
41. The incidence
The incidence of Down syndrome is
estimated at one per 800 to one per
1000 births.
In 2006, the Centers for Disease
Control and Prevention estimated the
rate as one per 733 live births in the
United States (5429 new cases per year)
42. Risk factors for DS
Older maternal age
Older paternal age
Already having a
child with DS
Carriers of the
genetic translocation
43. About 90 percent of pregnant
women who are given a Down
syndrome diagnosis have chosen
to have an abortion.
44. At maternal age 20 to 24, the
probability is one in 1562; at age 35
to 39 the probability is one in
214, and above age 45 the
probability is one in 19.
46. Prognosis for DS
Adults with good self-help skills
can be expected to live into
.
their 50s
Those with poor self-help skills
and live into their 40s.
Their lifespan continues to
increase
48. Treatments for DS
No medical cure
Specialist team
Care team
Early
intervention
Countinuing self-
help skills
49. Cafe down at Ankara
Waiters who are
with down
syndrome work at
this cafe
Although that’s not
new all over the
world,it is the only
and the first in
Turkey
50. They dont give up
so they are fulled-
hopefull
On the other
hand,having
motivational
support makes
the works better
51. March 21
The first World Down Syndrome Day was held on 21
March 2006
