CASE STUDY - Genetics Counseling Project - PKU
CASE STUDY – Genetics Counseling Project – Tay-Sachs
Kendra and Keith had a son and daughter and then another
daughter, Hallie. Unfortunately, a few months after her birth
they realize that Hallie isn’t developing her mental abilities the
way she should. She doesn’t seem to pick up the concept related
to picking up and playing with objects. After a series of tests it
was discovered that Hallie had Phenylketonuria.
Jacob and Elizabeth are enjoying the addition of Hannah to their
family. Hannah has a brother, Abe who is 10 and a sister, Mary
who is six. Hannah doesn’t appear to be growing at her two month
check up so the doctor orders a series of tests. Unfortunately,
they discover that Hannah has Tay-Sachs disease.
The doctors wanted to determine if this was a disorder Hallie
inherited or whether it was a genetic mistake, so Kendra and
Keith went back to their families to see if they could get any
answers. Keith has an older sister, Kathy, who has three children.
The boy is nine and the girls are six and they are normal. Keith’s
mom, Fran, had a younger brother who died at the age of 27 after
years in an institution for mentally challenged. Fran’s older
brother, Henry, married Ellen and they had four children, 2 boys
and then2 girls. The oldest son of Henry and Ellen has a son with
mental retardation. Keith’s dad, Otto can vaguely remember an
aunt who died at the age of 15 while in an institutional setting.
Fran’s parents, Emma and Frederick were both normal, as well as
all three brothers of Emma and the sister and brother of
Frederick. Kendra’s younger brother, Matthew is normal as is her
parents, Martha and Daniel.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
Jacob and Elizabeth are devastated by the news and turn to their
families for support. In response to their situation, the families
begin talking about some unexplained deaths in the past. One of
Jacob’s older sisters died at the age of four after several years
of decline in health. The other two sisters are normal. The
oldest sister, Kathleen is married and has two daughters and a son
who are also normal. The next to youngest sister, Ann is also
married and has a healthy son and daughter.
Elizabeth has a younger brother and two younger sisters all of
whom are normal. Elizabeth’s brother, Isaac is married with two
healthy sons. Hannah’s mother can’t recall any unusual happenings
in her family. Hannah’s father, Isaiah, has an older brother and a
younger sister. The brother married, Donna and they had a
daughter who died at the age of 5 ½. Isaiah’s sister never
married.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
CASE STUDY – Genetics Counseling Project – Muscular Dystrophy
CASE STUDY – Genetics Counseling Project - Hemophilia
Mike and Jane have an eight year old daughter who is healthy and
a six year old son who has just been diagnosed with Duchenne
Muscular Dystrophy. The doctors would like to know if any other
family members have had the disorder. Mike and Jane don’t
believe anyone in their families had DMD.
Jim and Tina have four children, ages 2 to 11. The oldest and
youngest are boys with the middle two being girls. The youngest
son, Forrest, is a normal toddler. He runs and jumps around like
all two year olds. The only problem is he seems to have more
bruises than most children do. They take Forrest to the
pediatrician and discover he has hemophilia. This is not a big
surprise to Jim and Tina as Tina has a brother, Justin, who has
hemophilia, yet they wonder if anyone else in their families are or
have been affected with this disorder.
They discover that Jane’s mother, Margaret, had a brother,
Frank, who waddled like a duck and died in his teens.
Margaret’s sister, June, also had a son who was confined to a
wheel chair at age 10 and died in his early twenties.
Mike’s mother, Betty, can’t recall any problems in her family or
her husband Bill’s. Betty does have two brothers and a sister who
are all normal.
Margaret remembers a little information about a maternal uncle,
Clarence, who died before the age of 15 after suffering from
severe muscle weakness for years.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
.
Tina has two other sisters, one who is single and the other is
newly married and none of them apparently have the disorder.
Tina’s mother, Donna, had a brother, Frank, who suffered from
bleeding problems and died in his late twenties.
Besides Frank, Donna has three other brothers and a younger
sister. Her brothers are all married. The oldest brother, Henry,
has three boys and they are normal. The third brother has one
daughter who also is normal. Yet the younger sister, Meg, has
three children, two girls and a boy, of which the son has
hemophilia.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
CASE STUDY – Genetic Counseling Project – Tay Sachs
CASE STUDY – Genetics Counseling Project – Cystic Fibrosis
Mary and Jacob have three children. Their oldest son, is 6, the
daughter is 2 and another son is six months old. They are
concerned about their two year old daughter who doesn’t seem to
be gaining weight like she should be. Their pediatrician sends
them to the University hospital for further testing. It is here
where several tests are conducted and it is determined that she
has Tay Sachs. This is extremely hard for Mary and Jacob to
understand, as they can’t recall anyone in their family dying from
this. Yet, they ask their families for additional information.
Lucia and David want to have a child. Lucia is concerned, however,
because she has a family history of cystic fibrosis. Lucia worries
about passing the disease to her child, even though she herself
does not have it. Lucia and David decide to consult a genetic
counselor to understand the risk of having a child with cystic
fibrosis.
Mary has two younger brothers, Abe and David. Abe is married to
Deb and they have a healthy set of twin daughters. David is not
married.
Mary’s parents, Isaac and Elizabeth each had a sibling who died
before they were five years old. Isaac’s brother, John died at
age 3½ after gradually becoming weaker and weaker during his
last few months. Elizabeth’s brother, Joseph died at age four of
a similar problem. Isaac has a married sister without children and
a brother who is married with two grown children. Elizabeth’s
only surviving sibling, Miriam, has two grown sons and a teenage
daughter. Miriam’s oldest son is married and they are expecting
their first child.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
Lucia has two brothers. Bryant is a 23-year-old graduate student
in microbiology. He has cystic fibrosis, although he didn't know
this until he was 8 years old. Before that, doctors simply treated
him for infection after infection--usually bronchitis or pneumonia.
He was terrified of catching a cold, which could land him in the
hospital. Bryant also had abdominal pains a few hours after eating,
and as a result, he was always severely underweight. Doctors
noted a "sensitive stomach" in his chart, lectured his mother on
providing proper nutrition, and attributed Bryant's pains to a
nervous disposition. A brother 2 years younger than Bryant
named Will was very healthy; but when a sister Katie was born
when Bryant was 8, a pattern appeared. Katie, like Bryant, battled
very frequent respiratory infections. When as a baby she would
scream after eating, doctors at first diagnosed colic and advised
switching infant formulas. Nothing helped. When, at two years of
age, Katie weighed only 20 pounds, her pediatrician began to put
together the symptoms with those of her elder brother. Bryant
and Katie were the only family members with the disorder.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
CASE STUDY – Genetics Counseling Project – Marfan’s Syndrome
Anne is 16 years old and is a junior in high school. Anne is 5' 11",
and wears contact lenses to correct for myopia (nearsightedness). She plays on her school's varsity volleyball and
basketball teams. NCAA scouts are already interested in her
playing ability and there is a chance she will be offered college
scholarships in both sports. Her armspan: height ratio is 1.08:1.
(In one group of 27 adults, this ratio was 1.006 with standard
deviation = 0.03.)
Anne has two siblings. David is age 25, married to Jessica, age
25, one daughter named Kristi, age 3 months. David wears glasses,
is 6' 3", has long fingers and toes, played basketball and ran track
in high school, had some knee problems that developed during his
high school athletic career. Jessica is 5' 8", no glasses, no health
complaints other than occasional migraine headaches. She and
David had one miscarried pregnancy in the first trimester before
the birth of Kristi. Anne’s sister, Cheryl is age 14, 5' 9", no
glasses, has a slight case of scoliosis. She was born with club feet
which responded well to corrective treatment.
Anne’s mother, Mary, age 47, 5' 7", wears glasses, has hay fever.
Has been diagnosed with carpal tunnel syndrome and mild
diabetes. Had two miscarriages in addition to her three children.
Her father, Peter, age 49, 6' 1", wears glasses, concave chest,
high blood pressure, partial lens dislocation in left eye, long
fingers and toes. Has complained about chronic tennis elbow.
Mary has three siblings. Dorothy, age 46, wears glasses, 5' 3", no
major health problems. Has had an ovarian fibroid tumor removed
at age 40. Married and has 4 children. Ellen, age 50, 5' 5", high
cholesterol, has been diagnosed with irritable bowel syndrome.
Ellen never married and does not have children. Eric, age 51, 6' 1",
wears reading glasses, has recurrent back problems from a car
accident, suffers from exercise-induced asthma. Eric is married
with two children from his first marriage and three from his
second.
Peter has four siblings. Frank, age 55, 6' 4", wears glasses, slight
hearing loss in one ear. Was treated for alcoholism, is a heavy
smoker and has developed a chronic cough. Divorced, the father
of 2 children. Peter’s sister, Alice, age 56, 5'7", wears glasses,
arthritis in left shoulder. Married, has one daughter and a son who
was born with cerebral palsy. John, deceased, heart attack at age
46, 6'2", had dislocated lens in right eye. He and his wife had
three children. Their youngest lives with his wife, who is still
living, as she is slightly mentally retarded. Peter’s other brother,
Larry , age 58, 6'3", no glasses, high blood pressure. Divorced
twice, lives alone now. Had two children by his first marriage and
one by his second. Is a heavy drinker.
Anne’s Maternal Grandmother, Evelyn, died at age 76 of stroke,
5'4", arthritis in hands and feet, wore reading glasses. Was said
to have had as many as 5 miscarriages. Evelyn’s husband William,
age 81, no glasses, 5'10", no major health problems. Has a slight
limp due to a bad right knee, occasional rashes, and hemorrhoids.
Anne’s paternal grandfather, Charlie, died at age 44 of a heart
attack, severe vision problems, described as long and lanky.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
CASE STUDY – Genetics Counseling Project – Fragile X
CASE STUDY – Genetics Counseling Project - Hemophilia
Darcy was learning disabled with an IQ at the lowest end of
normal. She finished high school, married, and started a family.
Her first son Sly was healthy.
Joanna is 28 years old and is thinking about starting a family. She
is concerned because her brother and a cousin on her mother's
side have hemophilia A. Her cousin is the son of her mother’s
sister, Hannah.
When Sly was two years old, Darcy and David had Barry. He was
developmentally delayed, not reaching milestones such as sitting
and standing when others his age would. He did not respond to
stimulation as a typically curious infant or toddler would. Odd
symptoms included a long face with coarse features, lopsided
large ears, and large testicles.
At Barry's one year check-up, the pediatrician asked if any family
members were mentally retarded or other children
developmentally delayed. Darcy mentioned her sister Marcy's 10month-old son Joseph who was not yet sitting.
They physician told them that he thought Barry might have
Fragile X syndrome, the most common form of inherited mental
retardation.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
Joanna is married to Frank and he too is concerned about
hemophilia as his older brother, Harry, died when he was 22 of
hemophilia related complications. He also has an aunt whose son,
Anthony, also has it.
In the 1980's Joanna had become convinced that when she
became pregnant, she would have prenatal diagnosis so that she
could discontinue the pregnancy if the fetus had inherited
hemophilia. She had based this decision on the anxiety she felt
that her brother might contract AIDS through the factor VIII
gene product clotting factor that he often received. According to
the National Hemophilia Foundation, a person with severe
hemophilia might encounter the blood of 100,000 people in just
one year by receiving donated clotting factor.
 In 1993, however, a form of factor VIII produced with
recombinant DNA technology became available, making
treatment much safer. The new clotting factor can, also, be
given preventively, greatly improving the quality of life for
those with hemophilia. Joanna's conviction to avoid having an
affected child began to change. But she still wants to know
whether or not she is a carrier.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
CASE STUDY – Genetics Counseling Project – Tourette Syndrome
 Mike and Carrie Riley had always attributed to simple
mischievousness the fact that four of their six children were
considered troublemakers in school. Greg and Ken had the
annoying habit of often repeating what was said to them, and
both boys had been punished for suddenly yelling out
obscenities in school. Alicia and Kate didn't yell, but they just
could not sit still in school, always fidgeting, jerking their
heads, blinking, and grimacing. So far, Joe and Cindy had no
such mannerisms. Since their father Mike and his mother Rita
also made these movements, everyone thought that the
children had just picked up their father and grandmother's
behavioral quirks from watching them.
 Mike's niece and nephew, Edie and Steve, children of his sister
Suzanne and her husband Adam, are generally healthy, but
have peculiar habits. Edie takes about twenty showers a day
and washers her hands dozens of times a day. Steve has
dyslexia and also has great difficulty solving mathematical
problems, such as balancing the checkbook and comparative
shopping at the supermarket. Their third child Jenny is only
two years old, and, so far, her behavior is normal.
 Carrie's sister Vicki is in medical school. When she learns
about Tourette syndrome, she immediately thinks of her
troublesome nieces and nephews.
CASE STUDY – Genetics Counseling Project – Sickle Cell Anemia
Two graduate students travel to Central America to conduct research of
wild corn, teosinte. While in Guatamala, one student, Maria Staiti, 4
months pregnant, becomes dehydrated because of the travel and
requires hospitalization. Another student, Derrick Hernandez contracts
malaria for which he is treated. In hospital, Maria learns she is a sickle
cell carrier.
Back home, Maria consults with sickle cell specialists and learns more
about sickle cell trait. Maria's husband, Derek, learns that he, too is a
carrier of sickle cell, and they seek genetic counseling for themselves
and their baby. They must decide whether to do prenatal testing and
about the options for that testing. They have many questions about
sickle cell trait and disease, and what the possibilities are for their
child.
The research they conduct, determines that Maria’s father, Enriqua, has
a mild form of the disorder. Maria’s mother, Theresa, does not have the
disorder, but knows that her father frequently suffered from shortness
of breath before his untimely death at the age of 42.
Derek’s parents seem to be normal, but they do some checking into their
family history. Derek’s mother seems to remember her mother having
difficulties with difficult work and was confined to simple chores in her
home. She died at the age of 37, after what seemed to be a normal
delivery of her 4th child.
Prepare a pedigree of the family. Using a punnett square and explanation
of the pattern of inheritance advise the family of the probabilities that
their future children may inherit the disorder.
CASE STUDY – Genetics Counseling Project – Huntington’s
Disease
John and Kelly Patterson just found out that they are going to
have a baby. They share concerns however about the possibility
that the child may develop a family disorder called Huntington’s
disease, so they visit a genetic counselor to determine the
likelihood of this possibility.
The genetic counselor gathers family background information.
John in his late 20s seems to be exhibiting some signs of
Huntington’s disease. His father, Lloyd, died at the age of 43.
Lloyd was one of 4 children – 3 boys and one girl. All other
siblings were normal. John never met his Grandmother, Ester, but
spent many summers with his Grandpa John who was now looking
forward to being a great-grandfather. Ester had 5 siblings, 3
Brothers – Fred, Ted and Ed and 2 Sisters, Myra and Cecelia.
Fred, Ed and Cecilia all died before their 45th birthdays.
Kelly’s parents June and Tom had 3 children – Rick, Sally and Kelly,
all of whom were healthy. Kelly’s Grandparents – both maternal
and paternal had healthy children.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
CASE STUDY – Genetics Counseling Project – Hemophilia
The bleeders disease is a disorder common to the Mariposa
family. Jose and Jeanie are discussing their desire start a family
but they are concerned about the possibilities that their children
may have hemophilia. They decide to visit a genetics counselor to
get some advice.
Jose can remember an uncle, Fernando, who often had to be
hospitalized to receive blood transfusions. Jose’s father, Juan,
never seemed to have that kind of problem, but Jose also
remembers that his often his grandfather - whom Jose had never
met – who was often hospitalized and died in a farming accident.
Jeanie is one of 4 children – all girls. The girls had a hard time
growing up and missed having their father around. Jeanie’s father
had always seemed reserved and sickly and was often in the
hospital in need of blood transfusions. Kristoff died at the age of
48, just after giving Jeanie away at her wedding. Kristoff had a
younger brother and an older sister, neither of whom showed any
of the same signs as Kristoff. Jeanie’s paternal grandparents,
Sven and Svetlana always told wonderful stories of the old
country. Jeanie recalled hearing her grandmother speak fondly of
two brothers who suffered from the bleeders disease and the
possibility that she might be distantly related to Russian Royalty.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
CASE STUDY – Genetics Counseling Project – Albinism
Tina and Jack have been married for 3 years and were anxious to
begin a new family and had a son, Joe, right away. They have just
found out that Tina is 10weeks pregnant with their second child.
The first pregnancy was unexpected and they ended up having a
son with Albino characteristics. They have decided to consult a
genetics counselor to determine what the chances of having a
second child with the condition might be. They are interested in
possible prenatal testing.
The genetics counselor has asked for them to bring a record of
family history. Jack has had a difficult time determining his
background as he grew up in foster homes and did not know his
real father. Jack did not display the condition – nor did his
mother, Sandy. Jack contacts Sandy through an agency and finds
out that Bill, Jack’s father, had an uncle who displayed albino
characteristics.
Tina has a younger sister, Tammy, and a brother, Randy. All are
normal. Tina’s Mom and Dad, Jan and Dan, are of normal
appearance, but Jan had an albino sister, Martha. Tina vaguely
remembers Aunt Martha, but did not know her well as she lived
way up North and did not like to visit the sunshine state too
often. Tina also recalls her mom speaking of a Grandfather who
showed albino characteristics.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
CASE STUDY – Genetics Counseling Project – Klinefelter’s
Syndrome
Pat and Fran Smith have just received some unfortunate news
from their doctor. They have been very excited about the arrival
of their first child and the news has been hard to take. They are
in the process of trying to determine how best to deal with the
problems that might arise for their child in the future and to
understand how this problem occurred.
As a genetic counselor it is your responsibility to inform the
family, in an understandable manner, how this disorder came
about. It is advisable to use diagrams illustrating non-disjunction
during meiotic divisions in addition to the likely karyotype of their
child. Explanation must accompany these diagrams.
Be sensitive to the fact that either Pat of Fran may feel that
they are to blame for this incident. Your job is to inform them,
reassure them and advise them of tests, treatments and research
available to cope with their situation.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
CASE STUDY – Genetics Counseling Project – Color Blindness
CASE STUDY – Genetics Counseling Project – Achondroplasia
Janalyn is devastated that she cannot pick out the flowers and
ribbons to match her wedding theme. She is red-green color blind
– a condition that is quite rare in women. Janalyn is marrying Alan
who seems to be able to distinguish colors quite well, but
unfortunately has no desire to get involved with flowers and
decorations. Janalyn and Alan want to consult a genetics
counselor in order to understand what chances their future
children will have of encountering similar problems. They have
been requested to bring along a family history.
Fred and Ginger Smith just found out that they are going to have a
baby. They are a unique couple who live in a very close knit
community of “little people.” Achondroplasia or Dwarfism is the
genetic condition that has brought them together. Fred and Ginger
are very excited about having their first child and they are open to
having a boy or a girl, one who shares their condition, or one who does
not.
Janalyn has a father with red-green color blindness. Emma Janalyn’s Mom - and Emma’s brother Charlie, had normal vision
while their father, Ed, - Janalyn’s Grandfather - was color blind.
Grandpa Ed’s two older brothers Tom and Barney are also redgreen color blind, though their little sister Carol had normal
vision.
Alan and his two sisters have normal vision, but his brother is
color blind. Neither of Alan’s parents are color blind, but Alan
seems to recall that his maternal (Mom’s Dad) Grandpa Joe had
trouble differentiating the lights he used to put up around the
house at Christmas time.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of
the probabilities that their future children may inherit the
disorder.
They are consulting a counselor to determine what possibilities there
would be of having a child who does not exhibit the traits common to
their disorder. There are many things to consider if their child is
normal. Will they have to modify their house? How will they manage
a physically larger child? How will the child be accepted by peers?
Etc. They have logical concerns but are excited by the prospect that
their child may have opportunities that have not necessarily been
forthcoming to them.
Their family history is as follows. Both Fred and Ginger were born of
one parent who displayed Dwarfism and one parent who did not.
Both of Fred’s parents Ed and Margerie displayed the condition, but
his Grandma Jane did not. He did not know his Grandpa, but had
heard he had been a popular circus performer – a clown of very small
stature.
Ginger’s Mom and grandparents live nearby. Her Dad was killed in a
car accident when she was young. He displayed the characteristics
of dwarfism. Her Mom, Freida and her Grandparents Don and Hazel
all showed normal development. Ginger also has a sister, Emma, who
shows normal development.
Prepare a pedigree of the family. Using a punnett square and
explanation of the pattern of inheritance advise the family of the
probabilities that their future children may or may not inherit
the disorder.
CASE STUDY – Genetics Counseling Project – Polydactyly
John and Kelly Patterson just found out that they are going to
have a baby. They share concerns however about the possibility
that the child may develop a family disorder called Polydactyly, so
they visit a genetic counselor to determine the likelihood of this
possibility.
As the genetic counselor you gather the following family
background information. John has two brothers, Ed and Tom, and
a Mom and Dad - Luis and Tina - none of whom show the
characteristic for Polydactyly. Kelly is an amazing pianist. She
can reach all of the keys easily and plays with phenomenal
technique. This is in part due to the fact that she has 5 fingers
and a thumb on one hand. Kelly has a sister Laura who was born
with an extra toe and a brother who was born with the correct
number of digits. Although Kelly’s mother does not display any
abnormalities, her father Jim has a scar from where an extra
digit on his hand was removed. In addition, Aunt Martha, Jim’s
sister was born with an extra toe. Kelly’s Grandma, Ella, was also a
pianist of great renowned as she had 6 digits on each of her
hands. Grandpa Ron had normal development.
Prepare a pedigree of the family history. Using a punnett
square and explanation of the pattern of inheritance advise
the family of the probabilities that their future children may
inherit the disorder.
CASE STUDY – Genetics Counseling Project –
Neurofibromatosis
John and Kelly Patterson just found out that they are going to
have a baby. They share concerns however about the possibility
that the child may develop a family disorder called
Neurofibromatosis, so they visit a genetic counselor to determine
the likelihood of this possibility.
As the genetic counselor you gather the following family
background information. John has two brothers, Ed and Tom, and
a Mom and Dad - Luis and Tina - none of whom show the
characteristic for Neurofibromatosis. Kelly has several freckles
on her body which are not exposed to the sunlight. She also has a
mild case of scoliosis. Kelly has a sister Laura who was born with
multiple café-au-lait spots and a brother who was born with
normal skin appearance. Although Kelly’s mother does not display
any abnormalities, her father Jim has a scar from where a tumor
was removed from his spinal cord several years ago. In addition,
Aunt Martha, Jim’s sister had significant hearing loss by the time
she was 30. Kelly’s Grandma, Ella, also suffered from painful
tumors on her body.
Prepare a pedigree of the family history. Using a punnett
square and explanation of the pattern of inheritance advise
the family of the probabilities that their future children may
inherit the disorder.