Down Syndrome
Introduction
Down Syndrome, also known as Down’s Syndrome (or Trisomy
21 in Europe), is a genetic disorder that affects roughly one in 800 live
births around the world. Generally
random, its causes remain unknown and untreatable. The effects of
Down Syndrome, which almost always includes a degree of mental retardation, vary
widely in severity, but when provided with a loving and understanding home environment,
DS children can flourish and become active particpants in their
community.
Basic Information
The condition known today as Down Syndrome was first described under the name of
‘Mongolism’ by an English physician, John Langdon Down in 1866.
Its root cause, a genetic abnormality, was not discovered until 1959.
Down Syndrome is the result of an error in cell division at, or soon after, the
mother’s egg is fertilised. Within
the nucleus of a typical human cell the genetic information is carried in
coded form on 23 pairs of chromosomes, spiral threads made up of DNA.
Cell division is an extremely complex process, and potentially subject
to many mishaps. In Down Syndrome
one of several errors in the division process results in chromosome 21 being
duplicated, the extra DNA subtly interfering with the biochemistry of normal
cell function.
In roughly 93 percent of cases the symptoms of Down Syndrome are caused by a
simple duplication of chromosome 21. However, there are two other less-common forms of DS, which
carry somewhat different consequences.
Translocation DS is the result of DNA from chromosome 21 becoming attached to another
chromosome. The practical
implication of this is that Translocation DS is an inheritable condition,
meaning that a couple whose offspring have it are at significantly greater
risk of having a second DS baby. For
this reason it is important that DS parents undergo genetic testing to
determine the nature of their condition.
When the duplication of chromosome 21 DNA occurs not at fertilisation, but
subsequently during early cell division, the result can be that only some
cells and not others carry the abnormality.
This results in ‘Mosaic Down Syndrome’, a condition found in 2-4
percent of cases. Because
the effects depend on which cells possess the extra DNA, the symptoms of
Mosaic DS are very diverse, but generally less severe that conventional DS.
Effects of Down Syndrome The effects of Down Syndrome may be divided into two categories –
physical and psychological.
The former include those characteristics whereby DS is generally recognised,
together with the medical problems that often accompany it.
The latter include the attitudes of society to individuals with DS, and more
particularly the impact that DS has on families in which the condition arises.
The facial and other physical characteristics typical of DS children, their
warm and loving
nature, or the mental retardation and learning difficulties that
that accompanies them, do not need to be elaborated on here, for they are
covered in detail on many websites.
Likewise attendant medical conditions in DS – heart
disease, hearing loss etc. – receive wide coverage.
In any case, these are subjects best discussed with paediatricians.
The psychological impact of Down Syndrome, however, does deserve our attention.
In many societies children with DS are considered a blight on the
family, to be shut away, neglected and as far as possible forgotten about.
For both the family and the child this is a catastrophe.
Fortunately this baleful attitude is shifting, particularly in the
West, and DS families and their children are often accepted by and fully
integrated into their local communities, with marked benefits for all
involved.
When DS children grow up in a loving family environment, instead of being shut away
anonymously in state institutions as in times past, their life expectancy
improves dramatically. Whereas in
the 1920s a DS child in the United States might have been expected to live
perhaps nine years, and in the 1940s thirteen years, today life expectancy has
risen to fifty years.
The family too benefits from nurturing a DS child in their midst, enjoying for
example, with special delight, the mastering of new skills, however delayed. Even
greater pleasure should be enjoyed through creating a more beneficial future
environment for the child by educating their community.
When DS children are viewed as ‘different’ or ‘less than’, it
is because society is ignorant – and ignorance breeds fear, which in turn
breeds rejection.
In times past, DS children were shut away, fuelling society’s fear through
unfamiliarity and hence ignorance. Today,
particularly within the United States, there is a growing understanding and
acceptance. DS children often
attend local schools, their limitations far outweighing their contributions in
other areas. Not least, children
growing up with a disabled individual in their midst acquire a valuable lesson
in compassion and humanity.
Given the opportunity, a child with Down Syndrome, however delayed its development
might be in some areas, frequently possesses gifts – in music, in art, and
elsewhere – that raises it above its companions.
The principle lesson to be learned is that nobody should be neglected or starved
of love and affection because they appear to have deficiencies.
Within every individual there exists the potential to make significant
contributions to society. Parents
can derive a unique pleasure through nurturing and discovering such special
gifts.
Links to some useful DS web sites
National
Down Syndrome Society: Welcome:www.ndss.org/
National
Association for Down Syndrome: www.nas.com/
Down
Syndrome: Health Issues - Medical Essays and Information: www.ds-health.com/
Down
's
Heart Group (UK): www.dhg.org.uk
Down's
Syndrome Association (UK): www.downs-syndrome.org.uk/
Down
Syndrome Information Network - Home Page: www.down-syndrome.info/
Down
Syndrome: For New Parents: www.downsyn.com/
Down
Syndrome Educational Trust - Home page: www.downsed.org/
Down
Syndrome Sites on the Internet:
www.ds-health.com/ds_sites.htm