genetic influences on health Flashcards
does the ovum or sperm head contain mitochondria
ovum
3 constitutive proteins
-globins
-dystrophin
-coagulation factors 8 and 9
constitutive protein: globin:
-mutated purpose
-resulting disorder
altered oxygen transport
-disorder: sickle cell, thalassemia
constitutive protein: dystrophin
-mutated purpose
-resulting disorder
muscle cell defect
-disorder: muscular dystrophies
constitutive protein: coagulation factors 8 and 9
-mutated purpose
-resulting disorder
abnormal clotting activity
-disorder: hemophilia type a and b
4 enzymes
-phenylalanine hydroxylase
-(hexA)
-HGPRT
-HMG-CoA reductase
enzyme: phenylalanine
-mutated purpose
-resulting disorder
interrupted metabolism, accumulation of toxic precursors
-disorder: phenylketonuria
enzyme: hexA
-mutated purpose
-resulting disorder
interrupted metabolism, accumulation of precursors
-disorder: tay-sachs disease
enzyme: HGPRT
-mutated purpose
-resulting disorder
disruption of metabolism, accumulation of uric acid
-disorder: lesch-nyhan syndrome
enzyme: HMG-CoA reductase
-mutated purpose
-resulting disorder
disruption of metabolism, accumulation of cholesterol
-disorder: familial hypercholesteremia
3 disorders caused by hereditary and environmental causes
-cancer
-single gene disorders (PKU)
-anomalies from prenatal environmental causes (amputation, cleft lip and palate)
examples minor anomolies
sacral dimple
extra nipple
cafe au lait spot
example of congenital anomaly that occurred in isolation
congenital heart defect
congenital anomalies: syndromes (2)
fetal alcohol syndrome
downs syndrome
congenital anomaly: association
VACTERL association
congenital anomaly: sequence
pierre robin
2 categories chromosome disorders
-structural abnormality: loss, addition, rearrangement, exchange; error in cell division
-numeric chromosome abnormality: entire chromosomes are added/deleted
uniform addition of chromosomes to all original pairs
euploidy
one chromosome is added/lost from one pair of chromosomes (not all)
aneuploidy
trisomy 21
down syndrome
trisomy 18
edwards syndrome
trisomy 13
patau syndrome
need to know specific chart of chromosomal genetic disorders??
what increases risk of development of trisomy 21
increased maternal age
S+S down syndrome
-delayed mental and social development
-impulsive behavior
-poor judgment
-short attention span
-slow learning
2 rare types down syndrome
-translocation down syndrome
-mosaic down syndrome
S+S edwards syndrome (trisomy 18)
-severe cognitive impairment
-short lifespan
-small mouth and jaw
-short neck
-prominent occiput
-malformed ears
-clenched hands with overlapping fingers
-flexed big toes, prominent heels
-short and prominent chest, wideset nipples
S+S patau syndrome (trisomy 13)
-short life span
-cleft lip/palate
-scalp defects
-low set ears
-severe mental retardation
-small eyes, head, jaw
-*brain, heart, kidney defects
3 sex chromosome aneuploidies
-47 XXY: klinefelter syndrome
-45 X0: turner syndrome
-47 XXX: triple x syndrome
S+S klinefelter syndrome (47 XXY)
-gynecomastia
-hypogonadism
-normal mental development
-tall
-osteoporosis
S+S turner syndrome (45 X0)
-clinical manifestations variable
-verbal IQ exceeds performance IQ
-girls usually infertile (no menstruation)
-no pre-pubertal growth spurt
-growth normal until 3 yo (short)
-brown spots
-folds of skin on neck (webbed look)
S+S triple x syndrome (47 XXX)
-normal appearance
-increased risk learning disabilities
-delayed menarche and premature menopause
-taller than average
-weak muscle tone
-behavioral and emotional difficulties
2 structural chromosome abnormalities
-46 XX(del 5p) or 46 XY(del 5p): cri du chat
-fragile x syndrome
S+S cri du chat (46 XX-del5p or 46 XY-del5p)
-moon shaped face
-wide set, downward slanted eyes
-profound cognitive impairment
-many die in infancy
-cry sounds like cat
-improves with age
-low birth weight, slow growth
-single line on palm of hand
-small head, small jaw
-skin tags in front of ear
S+S fragile x chromosome
-prominent/long ears
-long face
-delayed speech
-large testes
-hyperactivity
-gross motor delays
-autistic spectrum disorder
achondroplasia
dwarfism
marfans
really tall
heart and eye issues
huntington disease
causes movement, thinking, and psych problems
resembles dementia but in 30s/40s
rare genetic disorder that primarily affects growth of nerve cell tissue. causes nerve tumors and skin and bone change. caused by gene mutations on chromosome 17
neurofibromatosis (NF)
when do symptoms of neurofibromatosis show up
usually at birth, definitely by 10 yo
diagnostic criteria for neurofibromatosis (NF-1 and 2)
NF-1 (must have 2+):
->6 cafe au lait spots
->2 neurofibromas
-inguinal/axillary freckles
-optic glioma
->2 lisch nodules
-sphenoid dysplasia
-1st degree relative
NF-2:
bilateral 8th nerve masses or 2 of following:
-neurofibroma
-meningioma
-glioma
-schwannoma
-juvenile cataract
general S+S neurofibromatosis
-scoliosis
-cafe au lait spots
-bone deformities, break easily
-high BP
one whose phenotypic expression occurs only when both genes have disease associated mutations
recessive allele
one who doesn’t have the disease but is a carrier
heterozygous carrier
examples of diseases from autosomal recessive inheritance (3)
-sickle cell
-cystic fibrosis
-tay-sachs disease
do males or females have symptoms of x-linked recessive disorders
are males or females carriers
symptoms: males
carriers: females
examples x-linked recessive disorders (2)
-hemophilia a and b
-duchenne muscular dystrophy
do males or females have symptoms of x-linked dominant disorders
both
examples x-linked dominant disorders (2)
-hypophosphatemic vit D resistant rickets
-incontinentia pigmenti
indications for prenatal genetic testing: general risk factors
-maternal age 35+ at time of delivery
-maternal age 31+ if having twins
-elevated or low trisomy profile screen results
indications for prenatal genetic testing: specific risk factors
-previous child with defect/chromosomal anomaly
-previous stillbirth/neonatal death
-structural abnormality in mother/father
-balanced translocation in mother/father
-inherited disorders
-medical disease in mother (DM, PKU)
-exposure to teratogen
-infection (rubella, toxoplasmosis, CMV)
-abnormal ultrasound findings
what ethnic groups are more likely to develop tay-sachs disease (2)
-jewish
-french canadian
what ethnic groups are more likely to develop sickle cell anemia (5)
-black african
-mediterranean
-arab
-indian
-pakistani
what ethnic groups are more likely to develop a and b thalassemia (3)
-mediterranean
-southern and southeast asian
-chinese
assessment clues to genetic disorders: growth abnormalities
-short stature
-overgrowth
-asymmetrical growth
-IUGR
assessment clues to genetic disorders: skeletal
-limb abnormalities
-asymmetry
-scoliosis
-hyperflexibility
-hypotonic/hypertonic muscle tone
-pectus excavatum
-finger/joint abnormalities
assessment clues to genetic disorders: visual/hearing
-coloboma of iris
-hearing loss
-cataracts
assessment clues to genetic disorders: metabolic
unusual odor of:
-breath
-urine
-stool
assessment clues to genetic disorders: sexual development
-ambiguous genitalia
-micropenis
-delayed onset puberty
-primary amenorrhea
-precocious puberty
-large testicles
assessment clues to genetic disorders: skin
-unusual pigmentation (cafe au lait, vitiligo)
-dry and scaly skin
-skin tumors
-hyperextensible skin
assessment clues to genetic disorders: recurrent infection/immunodeficiency
-ear infection
-pneumonia
-poor healing umbilicus
assessment clues to genetic disorders: cognitive
-learning disabilities
-mild to severe cognitive impairment
assessment clues to genetic disorders: behavioral
-attention deficit with or without hyperactivity
-autistic behavior
-aggressive behavior
assessment clues to genetic disorders: major/minor birth defects and dysmorphic features
-cardiac defect
-ear/eye abnormalities
-micrognathia
-forehead prominence
-hairline low on forehead or nape of neck
-wide set eyes
-epicanthal folds
-low set/abnormal ears
