Transcript Genetic Disorders

GENETIC DISORDERS
Albinism- autosomal recessive trait
• http://www.youtube.com/w atch?v=r4q4V2LbzD0
• What is it?
• Albinism occurs when one of several genetic defects makes the
body unable to produce or distribute melanin, a natural substance
that gives color to your hair, skin, and iris of the eye.
• Symptoms
• Absence of color in the hair, skin, or iris of the eye
• Lighter than normal skin and hair
• Patchy, missing skin color
Sickle Cell Anemia
• http://www.youtube.com/watch?v=9UpwV1tdxcs
• http://www.youtube.com/watch?v=diwVfhx0Jfs
• What is it?
• Sickle cell anemia is from a mutated gene that is inherited via a
recessive allele. It is not sex-linked.
• Symptoms
• Sickle cell anemia is caused by an abnormal type of hemoglobin
called hemoglobin S. Hemoglobin is a protein inside red blood cells
that carries oxygen. Hemoglobin S changes the shape of red blood
cells, especially when the cells are exposed to low oxygen levels.
The red blood cells become shaped like crescents or sickles.
• The fragile, sickle-shaped cells deliver less oxygen to the body's
tissues. They can also get stuck more easily in small blood vessels,
and break into pieces that interrupt healthy blood flow.
Dwarfism
• What is it?
• Dwarfism refers to abnormally short height in
childhood due to the lack of growth hormone.
Growth hormone is produced in the pituitary gland,
located in the brain. Different hormones made in the
brain tell the pituitary gland how much growth
hormone is needed. Growth hormone enters the
blood and stimulates the liver to produce a hormone
called insulin-like growth factor (IGF-1), which plays
a key role in childhood growth.
• Growth hormone deficiency is not sex-linked
• Symptoms
Children with growth hormone deficiency:
• have a slow or flat rate of growth, usually
less than 2 inches per year.
• will be much shorter than children their age.
• may look much younger than their age
• puberty may come late or may not come at
all.
Gigantism
• What is it?
• Gigantism is abnormally large growth
due to an excess of growth hormone
during childhood, before the bone
growth plates have closed. The most
common cause of too much growth
hormone release is a noncancerous
(benign) tumor of the pituitary gland.
• Gigantism is not sex-linked and the
condition is extremely rare.
• Symptoms
• The child will grow in height, as well
as in the muscles and organs. This
excessive growth makes the child
extremely large for his or her age.
• Delayed puberty
• Large hands and feet with thick
fingers and toes
• Weakness
Progeria Video
• What is it?
• Autosomal recessive disorder
• Excessive aging- name
means “prematurely old”
• Symptoms present around
18-24 months of age.
• Symptoms
• Growth failure, loss of body
fat and hair, aged-looking
skin, stiffness of joints, hip
dislocation, generalized
atherosclerosis,
cardiovascular (heart)
disease and stroke.
• Fatal by age 13-20
Huntington's Chorea Video
• What is it?
• Autosomal dominant
• Neurodegenerative disorder
• Diagnosed in 40’s (most have
had children at this point and
passed trait on)
• Chorea means “to dance”
• Symptoms
• Cannot control movement of
limbs, then body, eventually
smooth muscles
• Death 10-15 years after
diagnosis
• Can take meds to slow
progress but not
cure…LETHAL
Turners Syndrome
• http://www.youtube.com/watch?v=ldjb-FR-PKo
• What is it?
• Turner Syndrome (TS) is a chromosomal condition that exclusively
affects girls and women. TS occurs when one of the two X
chromosomes normally found in females is missing or incomplete
• Symptoms
• Short stature
• Webbed neck
• Swollen hands and feet
• Infertility
• Kidney problems
• Congenital heart defects
Klinefelters Syndrome
• http://www.youtube.com/watch?v=UB
yxV4fw0Pc&feature=related
• What is it?
• Also known as the XXY condition,
Klinefelters syndrome is a chromosomal
condition in which males have an extra X
chromosome,.
• Symptoms
• Low testosterone
• Tend to have language difficulties
• Can have other health issues such as
increased risk for osteoporosis and
autoimmune diseases
• Most are infertile
Down Syndrome
• http://video.about.com/pediatrics/Do
wn-Syndrome.htm
• http://www.youtube.com/watch?v=-_P4t2jR1g
• What is it?
• Also known as Trisomy 21, people with
Downs Syndrome have 3 copies of
chromosome instead of 2
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Symptoms
Flattened facial features
Upward slanting eyes
Poor muscle tone
Mild to moderate mental retardation