Genetic Disorders

Question 1

Genotype

Answer 1

entire genetic compesition

Question 2

Phenotype

Answer 2

outward expression of genes

Question 3

Chromosomal Karyotyype

Answer 3

chromosomal map from a single cell

Question 4

Somatic cells of the body

Answer 4

23 pairs of chromosomes
one pair of sex chromosomes
(XX-female, Xy-male
22 pairs of autosomes

Question 5

Karyotypes

Answer 5

46,XX
46, XY
46, XY -10q
47, XX, +21

Question 6

Monosomy

Answer 6

• when a chromosome of a pair is missing

Question 7

Translocation

Answer 7

part of chromosome has detached during myosis, may lead to deletion from one chromosome and reattachment to another chromosome

Question 8

Deletion

Answer 8

part of chromosome is missing;part of genetic code has been omitted

Question 9

Trisomy

Answer 9

presence of extra chromosome

Question 10

Trisomy 21

Answer 10

down syndrome

Question 11

Incidence of DS

Answer 11

1/100 live births
App 5,000 infants born with down syndrome born every year
risk increases with maternal age

Question 12

physical characteristic of Down Syndrome

Answer 12

low muscle tone
macroglossia
micrognathia
speckling of iris
epicentral fold of eyes
saddle nose
small ears
small stature
upward slant of eyes
simian crease
wide gap b/t toes 1& 2

Question 13

Down Syndromes relation to ligamentous instability

Answer 13

AA instability-could lead to cord injury, damage to brainstem, death

Question 14

Pathophysiology of trisomy 21

Answer 14

non-disjunction (95%)
translocation (4%)
Mosaicism (1-2%)

Question 15

Clinical picture of Down Syndrome

Answer 15

• simplicity in convolutional pattern (sulk/gyri)
• reduced synaptogenesis
• lack/delay of myelination
• dec # of small neurons
• structural abnormalities
• inc # neurofibrillary tangles & senile plaques

Question 16

Clinical picture of DS

Answer 16

• MR or cognitive impairment
• microbrachycephaly
• cardiopulmonary abnormalities
• developmental delay
• seizures, leukemia, duodenal atresia/stenosis, senile dementia

Question 17

Musculoskeletal presentations of DS

Answer 17

• hypotonia
• muscular variations
• foot deformities (yes planes)
• hip subluxation/dislocation
• patellar instability
• scoliosis
• A/A instability

Question 18

Sensory deficits of DS

Answer 18

hearing loss

• stabismus (esotria-inward turn of eye)
• cataracts
• chronic otitis media
• nystagmus
• myopia (near sited)

Question 19

Medical/Surgical management of DS

Answer 19

plastic surgery

stabilizing of hip, knee, ankle instabilities

Question 20

Edwards syndrome

Answer 20

2 most common trisomy w/ more serious organic malfunction
47XY +18
47XX+18

Question 21

Incidence of Edwards syndrome

Answer 21

• 1:8000 live births
• females >males 3:1
• only 10% of children survive past 10y/o

Question 22

Clinical presentation of Edwards syndrome

Answer 22

• LBW, small stature
• CV/GI/urogenital/skeletal malformations
• skull is long A-P and short M-L, misshapen ears, high tone, profound MR

Question 23

Trisomy 13 Patau Syndrome

Pathophysiology

Answer 23

trisomy of 13

less than 5% survive past 3 yrs of age

Question 24

Incidence of Patau syndrome

Answer 24

1:20,000 live births, correlated with advanced maternal age

Question 25

Clinical presentation of pate syndrome

Answer 25

CNS/CV/MS/urogenital malformations, severe/profound MR,anopthalmia/microopthalmia

Question 26

Medical management of Patau syndrome

Answer 26

Supportive: assisting family w/ positioning, feeding, management of hydrocephalus, seizures