Birth Defects
April 13, 2015
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The King and the Scratched Diamond…
Once there was a king who had a beautiful, large pure
diamond. There was no other diamond like it in the
world. One day, it became deeply scratched. The king
told his best diamond cutters, “I’ll promise you a great
reward if you can remove the imperfection from my
jewel.” But they could not. The king was very upset.
Many months later, a man came to the king. He promised
to make the diamond even more beautiful than it ever
had been. Impressed by the man’s confidence, the king
consented. He watched as the man engraved an
exquisite rosebud around the blemish and used the
scratch to make its stem.
--Parable of the Preacher of Dubno from Jewish Folklore
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Birth Defects
• This story can easily be related to birth defects. Even
though a child with a birth defect may not appear to be
perfect, he/she still has great abilities and opportunities
to apply him/herself in life. Rather than emphasizing the
problem, we must focus on the abilities of the person.
• Birth defect:
– An abnormality that affects the structure or function of the
body.
– Everyone is born with some type of imperfection.
– Most, like a birthmark, are relatively minor.
– Some are born with more serious problems. These are referred
to as birth defects.
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Factors that Influence Birth Defects
• Heredity
• Environment
• A combination of heredity and the environment
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Causes of Birth Defects
• Differ greatly!
• Caused by…
– Inherited from one or both parents.
– Controllable factors in the environment.
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Environmental Factors
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Diet
Diseases or infections of the mother
Harmful substances ingested by the mother
Exposure to outside hazards such as radiation
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Detecting Birth Defects
• Amniocentesis:
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Not a routine procedure
Long needle inserted into the uterus.
Amniotic fluid is removed and tested
3-4 weeks to get results
Involves risk of infection, and causing the body to abort the fetus
Only used when there is a valid medical reason, Down’s Syndrome
• Ultrasound:
– Imaging procedure in which sound waves are bounced off of the fetus to
produce a picture.
– Can show the development of a fetus and can detect certain defects
• Chorionic Villus Biopsy:
– Done under extremely serious conditions.
– Samples of villi (contained in the membrane containing amniotic fluid) are
snipped or suctioned off for analysis.
• If one of these tests indicates that a developing child has problems,
the couple can confer with their doctor and decide what to do.
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Helping to Prevent Birth Defects
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Early and regular prenatal care
Vaccines
Rh vaccine during pregnancy
Consult with genetic services
Become educated
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Hemophilia
• Hemophilia (heem-o-FILL-ee-ah) is a rare,
inherited bleeding disorder in which your
blood doesn’t clot normally.
• If you have hemophilia, you may bleed for a
longer time than others after an injury. You
also may bleed internally, especially in your
knees, ankles, and elbows. This bleeding
can damage your organs or tissues and,
sometimes, be fatal.
• About 18,000 people in the United States
have hemophilia. Each year, about
400 babies are born with the disorder.
Hemophilia usually occurs only in males
(with very rare exceptions).
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Sickle Cell Anemia
• Sickle cell anemia is an inherited blood disorder
that mostly affects people of African ancestry.
• A blood disorder that affects hemoglobin.
• Sickle cell anemia occurs when a person
inherits two abnormal genes (one from each
parent) that cause their RBCs to change shape.
Instead of being flexible and disc-shaped, these
cells are more stiff and curved in the shape of
the old farm tool known as a sickle.
• Sickle cells tend to clump together, making red
blood cells sticky, stiff, and more fragile. These
sickle cells can clog blood vessels and deprive
the body's tissues and organs of the oxygen
they need to stay healthy.
• Unlike normal RBCs that last about 4 months in
the bloodstream, fragile sickle cells break down
after only about 10 to 20 days, which usually
causes anemia.
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PKU (Phenylketonuria)
• Phenylketonuria (PKU) is an recessive
genetic disorderr characterized by a
deficiency in the enzyme phenylalanine
hydroxylase (PAH).
• This enzyme is necessary to metabolize the
amino acid phenylalanine to the amino acid
tyrosine. When PAH is deficient,
phenylalanine accumulates and is converted
into phenylketones, which are detected in
the urine.
• Left untreated, this condition can cause
problems with brain development, leading
to progressive mental retardation and
seizures. However, PKU is one of the few
genetic diseases that can be controlled by
diet. A diet low in phenylalanine and high in
tyrosine can bring about a nearly total cure.
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Down’s Syndrome
• Down syndrome (DS) is a condition in which extra
genetic material causes delays in the way a child
develops, and often leads to mental retardation. It
affects 1 in every 800 babies born.
• Normally, at the time of conception a baby inherits
genetic information from its parents in the form of
46 chromosomes: 23 from the mother and 23 from
the father. In most cases of Down syndrome,
however, a child gets an extra chromosome - for a
total of 47 chromosomes instead of 46. It's this extra
genetic material that causes the physical and
cognitive delays associated with DS.
• The symptoms of Down syndrome can vary widely
from child to child. While some kids with DS need a
lot of medical attention, others lead very healthy and
independent lives.
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Polydactyl
• A congenital anomaly consisting of
supernumerary fingers or toes. Each
hand or foot has six digits.
• Although the condition is usually not
life-threatening or even particularly
debilitating, most people in Western
societies have the extra digits removed
surgically.
• The extra digit is usually a small piece of
soft tissue; occasionally it may contain
bone without joints; rarely it may be a
complete, functioning digit.
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Color Blindness
• Color blindness, or color vision
deficiency, in humans is the inability
to perceive differences between
some or all colors that other people
can distinguish. It is most often of
genetic nature, but may also occur
because of eye, nerve, or brain
damage, or due to exposure to
certain chemicals.
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Cooley’s Anemia (Thalassemia)
• Thalassemia is an inherited blood disorder that
causes mild or severe anemia. The anemia is due to
reduced hemoglobin and fewer red blood cells than
normal.
• The most severe form of alpha thalassemia is
known as alpha thalassemia major. It can result in
miscarriage.
• The severe form of beta thalassemia is also known
as Cooley’s anemia.
• The most common treatment for all major forms of
thalassemia is red blood cell transfusions. These
transfusions are necessary to provide the patient
with a temporary supply of healthy red blood cells
with normal hemoglobin capable of carrying the
oxygen that the patient's body needs.
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Huntington’s Disease
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HD results from genetically programmed degeneration of nerve cells, called neurons, in certain
areas of the brain. This degeneration causes uncontrolled movements, loss of intellectual faculties,
and emotional disturbance.
Individual experiences mood swings or becomes uncharacteristically irritable, apathetic, passive,
depressed, or angry.
HD may affect the individual's judgment, memory, and other cognitive functions. Early signs might
include having trouble driving, learning new things, remembering a fact, answering a question, or
making a decision.
In some individuals, the disease may begin with uncontrolled movements in the fingers, feet, face,
or trunk.
The disease can reach the point where speech is slurred and vital functions, such as swallowing,
eating, speaking, and especially walking, continue to decline. Some individuals cannot recognize
other family members. Many, however, remain aware of their environment and are able to express
emotions.
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Tay-Sachs
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A baby with Tay-Sachs disease is born without one of the important enzymes, that
clear out fatty protein and other unwanted material that can interfere with
growth. As those fatty proteins build up in the brain, they hurt the baby's sight,
hearing, movement, and mental development.
Each year, about 16 cases of Tay-Sachs are diagnosed in the United States.
Although Jews of central and eastern European descent are at the highest risk for
the disease, it is now also prevalent in non-Jewish populations, including people of
French-Canadian/Cajun heritage.
A baby born with Tay-Sachs develops normally in the first 3 to 6 months of life.
During the next months the baby will progressively lose the ability to see, hear,
and move. A red spot will develop in the back of the child's eyes. The child will
stop smiling, crawling, turning over, and reaching out for things. By the age of 2,
the child may have seizures and become completely disabled. Death usually occurs
by the time the child is 5 years old.
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Cystic Fibrosis
• Cystic fibrosis is an inherited chronic
disease that affects the lungs and digestive
system of about 30,000 children and adults
in the United States (70,000 worldwide). A
defective gene and its protein product
cause the body to produce unusually thick,
sticky mucus that:
– Clogs the lungs and leads to life-threatening
lung infections; and
– Obstructs the pancreas and stops natural
enzymes from helping the body break down
and absorb food.
• In the 1950s, few children with cystic
fibrosis lived to attend elementary school.
Today, many people with the disease can
now expect to live into their 30s, 40s and
beyond.
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Cleft Lip/Palate
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Cleft palate
Cleft palate occurs when the roof of the mouth does not
completely close, leaving an opening that can extend into
the nasal cavity.
The cleft may involve either side of the palate. It can
extend from the front of the mouth (hard palate) to the
throat (soft palate). Often the cleft will also include the lip.
Cleft palate is not as noticeable as cleft lip because it is
inside the mouth. It may be the only abnormality in the
child, or it may be associated with cleft lip or other
syndromes. In many cases, other family members have
also had a cleft palate at birth.
Cleft lip
Cleft lip is an abnormality in which the lip does not
completely form during fetal development. The degree of
the cleft lip can vary greatly, from mild (notching of the lip)
to severe (large opening from the lip up through the nose).
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Club Foot
• Clubfoot or talipes is a congenital
deformity of the foot that occurs in
approximately 1:1000 births with half of
them being bi-lateral (both feet) and it is
twice as common in boys as in girls. The
foot has a typical appearance of pointing
downwards and twisted inwards. Since the
condition starts in the first trimester
of pregnancy, the deformity is quite
established at birth, and is often very rigid.
• Treatment options:
– Serial Plaster Casting
– Splints
– Non-Surgical Treatment Methods
• Ponseti Method
• French Physiotherapy Method
• Botox - botulinum toxin
– Surgery
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Type 1 Diabetes
• A form of diabetes which has its onset in childhood. Also
referred to as type I diabetes, juvenile onset diabetes or
insulin-dependent diabetes. The exact cause is unknown but
genetic factors seem to play a major role.
• Symptoms include excessive thirst, increased urination,
weight loss (despite increased appetite), nausea, vomiting,
fatigue and absent menstruation.
• Treatment includes education and regular insulin therapy.
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Hydrocephalus
• Also called: Water on the brain
• Hydrocephalus is the buildup of too much cerebrospinal fluid in the
brain. Normally, this fluid cushions your brain. When you have too
much, though, it puts harmful pressure on your brain.
• Symptoms of acquired hydrocephalus can include:
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Headache
Vomiting and nausea
Blurry vision
Balance problems
Bladder control problems
Thinking and memory problems
• Hydrocephalus can permanently damage the brain, causing
problems with physical and mental development. If untreated, it is
usually fatal. With treatment, many people lead normal lives with
few limitations. Treatment usually involves surgery to insert a
shunt.
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Marfan’s Syndrome
• Marfan syndrome is a heritable condition that
affects the connective tissue. In Marfan
syndrome, the connective tissue is defective and
does not act as it should.
• Marfan syndrome affects men, women, and
children, and has been found among people of all
races and ethnic backgrounds. It is estimated
that at least 1 in 5,000 people in the United
States have the disorder.
• Marfan syndrome affects different people in
different ways. The body systems most often
affected by Marfan syndrome are:
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Skeleton
Eyes
Heart and blood vessels (cardiovascular system)
Nervous system
Skin
Lungs
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Muscular Dystrophy
• Muscular dystrophy (MD) is a genetic disorder that
weakens the muscles that help the body move.
People with MD have incorrect or missing
information in their genes, which prevents them
from making the proteins they need for healthy
muscles.
• MD weakens muscles over time, so children, teens,
and adults who have the disease can gradually lose
the ability to do the things most people take for
granted, like walking or sitting up. Someone with
MD might start having muscle problems as a baby
or their symptoms might start later. Some people
even develop MD as adults.
• The life expectancy for many of these forms of
muscular dystrophy depends on the degree to
which a person's muscles are weakened as well as
how much the heart and lungs are affected.
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Spina Bifida
• Spina bifida is a birth defect that involves the incomplete
development of the spinal cord or its coverings. The term spina
bifida comes from Latin and literally means "split" or "open" spine.
• Spina bifida occurs at the end of the first month of pregnancy when
the two sides of the embryo's spine fail to join together, leaving an
open area. In some cases, the spinal cord or other membranes may
push through this opening in the embryo's back. The condition can
typically be detected before a baby is born and treated right away.
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Acondroplasia (Dwarfism)
• A genetic disorder of bone growth
that is evident at birth. It affects
about one in every 20,000 births
and it occurs in all races and in both
male and female genders. It is
estimated that there are about
10,000 individuals with this disorder
in the United States.
• When a person has Acondroplasia,
abnormal cartilage at the growth
plates of the bones in the body
causes their short stature. Men with
this disorder are usually less than 52
inches tall and women are
somewhat shorter.