NUR 529 - EXAM 1 (GENETICS)
QUESTIONS WITH COMPLETE
OPTIONS
treatment of PKU ✅✅ANSW-special diet that restricts phenylalanine intake (must be started as a
neonate (7-10 days) to prevent brain damage)
Tay-Sachs disease ✅✅ANSW-lysosomal storage disease (gangliosides) - failure to break down
GM2 gangliosides of cell membrane, causing accumulation in all organs (prominent in brain neurons
and retina) that leads to progressive destruction of neurons, including the cerebellum, basal ganglia,
brain stem, spinal cord, and autonomic NS
physical exam finding with tay-sachs ✅✅ANSW-cherry red spot on macula
how does tay-sachs present ✅✅ANSW-infants appear normal at birth but manifest progressive
weakness, muscle flaccidity, and decreased responsiveness at 6-10 months, followed by rapid
deterioration of motor and mental functioning (leads to seizures, blindness, death by age 4-5)
Tay Sach's pattern of inheritance ✅✅ANSW-autosomal recessive
population with higher level of tay-sachs ✅✅ANSW-Eastern European (Ashkenazi) Jews
pattern of inheritance in x-linked recessive disorders ✅✅ANSW-unaffected mother is carrier (not
affected bc she has normal X that is dominant over mutant recessive x) gives birth to sons who each
has a 50% chance of inheriting the mutant x and daughters who have 50% chance of becoming
carriers
when the affected son procreates, he will pass the mutant gene to 100% of his daughters (who get
his only X) and none of his sons will be affected (bc they inherit his Y)
x-linked recessive disorders affect ___ more than ____ ✅✅ANSW-males more than females
, x-linked dominant disorders pattern of inheritance ✅✅ANSW-affected females that are
heterozygous with one mutant X and one normal X will transmit the disorder to 50% of their
offspring regardless of sex (many times mutation will be embryonically lethal for males)
affected males will have 100% affected daughters and or 100% normal sons
eg Fragile X, Rett sydrome
fragile X syndrome ✅✅ANSW-single gene disorder that causes intellectual disability, most
common form of inherited intellectual disability
characteristics of fragile X syndrome ✅✅ANSW-long face with large mandible and long, everted
ears, hyper extensible joints, high-arch palate, mitral valve prolapse
diagnosis of fragile x ✅✅ANSW-based on mental and physical characteristics
DNA tests can be done to confirm presence of abnormal FMR1 gene
those with intellectual disability of unknown cause should be evaluated
Down syndrome ✅✅ANSW-a condition of intellectual disability and associated physical disorders
caused by an extra copy of chromosome 21.
what is associated with risk of having child with Down syndrome? ✅✅ANSW-increases with
maternal age
physical characteristics of Down syndrome ✅✅ANSW-small, square head, flat facial profile,
epicanthal folds (folds on inner corner of eyes), upward slanting eyes, small lowest ears, fat pad at
back of neck, large protruding tongue, single palmar (simian) crease, congenital heart defects*,
increased GI malformations*, increased risk for Alzheimers disease*
how is Down syndrome diagnosed in utero ✅✅ANSW-screened via blood tests together with
mom's age
QUESTIONS WITH COMPLETE
OPTIONS
treatment of PKU ✅✅ANSW-special diet that restricts phenylalanine intake (must be started as a
neonate (7-10 days) to prevent brain damage)
Tay-Sachs disease ✅✅ANSW-lysosomal storage disease (gangliosides) - failure to break down
GM2 gangliosides of cell membrane, causing accumulation in all organs (prominent in brain neurons
and retina) that leads to progressive destruction of neurons, including the cerebellum, basal ganglia,
brain stem, spinal cord, and autonomic NS
physical exam finding with tay-sachs ✅✅ANSW-cherry red spot on macula
how does tay-sachs present ✅✅ANSW-infants appear normal at birth but manifest progressive
weakness, muscle flaccidity, and decreased responsiveness at 6-10 months, followed by rapid
deterioration of motor and mental functioning (leads to seizures, blindness, death by age 4-5)
Tay Sach's pattern of inheritance ✅✅ANSW-autosomal recessive
population with higher level of tay-sachs ✅✅ANSW-Eastern European (Ashkenazi) Jews
pattern of inheritance in x-linked recessive disorders ✅✅ANSW-unaffected mother is carrier (not
affected bc she has normal X that is dominant over mutant recessive x) gives birth to sons who each
has a 50% chance of inheriting the mutant x and daughters who have 50% chance of becoming
carriers
when the affected son procreates, he will pass the mutant gene to 100% of his daughters (who get
his only X) and none of his sons will be affected (bc they inherit his Y)
x-linked recessive disorders affect ___ more than ____ ✅✅ANSW-males more than females
, x-linked dominant disorders pattern of inheritance ✅✅ANSW-affected females that are
heterozygous with one mutant X and one normal X will transmit the disorder to 50% of their
offspring regardless of sex (many times mutation will be embryonically lethal for males)
affected males will have 100% affected daughters and or 100% normal sons
eg Fragile X, Rett sydrome
fragile X syndrome ✅✅ANSW-single gene disorder that causes intellectual disability, most
common form of inherited intellectual disability
characteristics of fragile X syndrome ✅✅ANSW-long face with large mandible and long, everted
ears, hyper extensible joints, high-arch palate, mitral valve prolapse
diagnosis of fragile x ✅✅ANSW-based on mental and physical characteristics
DNA tests can be done to confirm presence of abnormal FMR1 gene
those with intellectual disability of unknown cause should be evaluated
Down syndrome ✅✅ANSW-a condition of intellectual disability and associated physical disorders
caused by an extra copy of chromosome 21.
what is associated with risk of having child with Down syndrome? ✅✅ANSW-increases with
maternal age
physical characteristics of Down syndrome ✅✅ANSW-small, square head, flat facial profile,
epicanthal folds (folds on inner corner of eyes), upward slanting eyes, small lowest ears, fat pad at
back of neck, large protruding tongue, single palmar (simian) crease, congenital heart defects*,
increased GI malformations*, increased risk for Alzheimers disease*
how is Down syndrome diagnosed in utero ✅✅ANSW-screened via blood tests together with
mom's age
