Hereditary Influences on Health of the Child and Family

Question 1

Genetic influences on health

Answer 1

-Hereditary-environmental interplay in diseases
-Genetic predisposition activated by environmental trigger
-Multifactorial diseases: can be mild or severe/deadly

Question 2

Pharmacogenetics/pharmacogenomics

Answer 2

-Pharmacogenetics: study of single genes that influence a med’s intended effect and risk for adverse outcomes
-Pharmacogenomics: study of portion of genome that contributes to medication response
-Variations in genes predispose a person to experiencing unintended effects from normal doses of certain medications
-Allows individualized medication selection and dosing to improve efficacy and safety

Question 3

Genetic disorders caused by chromosome abnormalities

Answer 3

-Single gene: PKU
-Cancers

Question 4

Anomalies from prenatal environmental causes

Answer 4

-Congenital amputation caused by amniotic bands
-Cleft lip and palate

Question 5

Chromosome disorders definition

Answer 5

Deviation in structure or # of a chromosome

Question 6

Chromosome disorder origin

Answer 6

-Duplication of genetic material
-Loss of genetic material: monogenetic (CF, huntington’s disease) or polygenetic (diabetes, HTN)

Question 7

Structural abnormality meaning

Answer 7

-Loss, addition, rearrangement, or exchange of genes of a chromosome
-Usually result from an error in cell division in sperm or ovum (parents are normal)

Question 8

Numeric chromosome abnormalities

Answer 8

-Occur whenever entire chromosome are added or deleted
-Euploidy: uniform addition of chromosomes to all the original pairs
-Trisomy: additional chromosome
-Monosomy: deletion of 1 chromosome (most types incompatible w/ life)

Question 9

Chromosome instability syndrome meaning

Answer 9

-Heterogenous group of disorders –> high breakage of chromosomes
-Associated w/ decreased immune fxn
-Associated w/ increased risk of cancer

Question 10

Chromosome instability syndrome examples

Answer 10

-Ataxia telangiectasia
-Fanconi anemia
-Xeroderma pigmentosum

Question 11

Autosomal inheritance patterns meaning

Answer 11

-Numeric alterations affecting autosomes
-Often recessive

Question 12

Autosomal inheritance patterns examples

Answer 12

-Trisomy 21 (down syndrome)
-Trisomy 18 (edwards syndrome)
-Trisomy 13 (patau syndrome)

Question 13

Down syndrome: trisomy

Answer 13

-92% of all cases
-Women is 47, XX, 21
-Me is 47, XY, 21
-Extra chromosome 21 is unattached and segregates freely during meiosis
-Risk for this type increases w/ age

Question 14

Down syndrome: translocation down syndrome

Answer 14

-4% of all cases
-Male robertsonian translocation between acrocentric chromosomes 14 and 21 is 46, XY, t (14, 21)
-Most cases are w/o family hx
-Approximately 25% have 1 balanced translocation carrier parent

Question 15

Down syndrome: mosaic down syndrome

Answer 15

-Rare cases
-Women w/ mosaic down syndrome is 46, XX/47, XX, 21
-Results from mitotic nondisjunction during early embryonic development of a normal zygote
-Affected children have mixed cell populations, some w/ the normal karyotype, others w/ the extra chromosome
-Proportion of trisomic cells affects child’s developmental potential and syndrome-associated potential health problems

Question 16

Trisomy 18

Answer 16

-Edwards syndrome
-Severe cognitive impairment and physical abnormalities
-Short life span

Question 17

Trisomy 13

Answer 17

-Patau syndrome
-Severe malformations = greater gene imbalance
-Short life span

Question 18

Sex chromosome aneuploidies

Answer 18

-Alteration in the # of sex chromosomes
-Profound effects are rare
-May have decreased intelligence or learning disabilities
-Turner syndrome = women look more masculine
-Klinefelter syndrome = men look more feminine

Question 19

X-linked recessive inheritance

Answer 19

-Usually affects males
-All carrier females are normal
-All affected males have s/s of the disorder
-Males are not carriers

Question 20

Disorders of the intrauterine environment

Answer 20

-Teratogens
-Inborn errors of metabolism (IEMs)
-Disruption in metabolic pathways
-PKU
-Galactosemia
-Molecular dx techniques
-Care mgmt

Question 21

Therapeutic mgmt of genetic disease

Answer 21

-Identify phenotype –> phenotype modification
-Surgery
-Diet (like in PKU)
-Avoidance of drugs
-Transplantation
-Gene product replacement
-Gene transfer
-Environmental modification

Question 22

Genetic testing categories

Answer 22

-Dx testing
-Screening (prenatal and newborn): provides early recognition, identify carriers, obtain population data and natural hx or genetic variations

Question 23

Genetic evaluation and counseling

Answer 23

-Genetic services (counseling)
-Estimation of risks
-Communicating risks

Question 24

Family hx constructed by the nurse

Answer 24

-Pedigree chart
-Family tree
-Genogram