ch 24 medical genetics Flashcards
personalized medicine
the use of information about a patient’s genotype and other clinical data in order to select a medication, therapy, or preventative measure that is specifically suited to that patient
monozygotic (MZ) twins
twins that are genetically identical because they were formed from the same sperm and egg
dizygotic (DZ) twins
(also known and fraternal twins) twins formed from separate pairs of sperm and egg cells
concordance
in genetics, the degree to which a trait or disorder is inherited, determined by how many pairs of twins both exhibit it
age of onset
the age at which symptoms of a disease first appear
simple mendelian inheritance
an inheritance pattern involving simple, dominant/recessive relationships that produce observed ratios in the offspring that readily obey mendel’s laws
haploinsufficiency
the phenomenon in which an individual has only a single functional copy of a gene and that single functional copy does not produce a normal phenotype; shows a dominant pattern of inheritance
gain-of-function mutation
a mutation that changes a gene product so that it gains a new or abnormal function
dominant-negative mutation
a mutation that produces an altered gene product that acts antagonistically to the normal gene product; shows a dominant pattern of inheritance
locus heterogeneity
the phenomenon in which a particular type of disease or trait may be caused by mutations in two or more genes
haplotype
the linkage of particular alleles or molecular markers on a single chromosome
founder
with regard to genetic diseases, an individual who lived many generations ago and was the person in which the disease-causing allele originated
linkage disequilibrium
phenomenon that exists when alleles and molecular markers are associated with each other at a frequency that is significantly higher than expected by random chance
genome-wide association study (GWA or GWAS)
an examination of a genome-wide set of genetic variants among many different individuals to see if any variant is associated with a disease or other type of trait
genetic testing
the use of testing methods to analyze an individual’s genes or gene products; in many cases, the goal is to determine if the individual carries a genetic abnormality
genetic screening
the use of testing methods at the population level to determine if individuals are heterozygous carriers for or have a genetic disease
amniocentesis
a method of obtaining cellular material from a fetus for the purpose of genetic testing
chorionic villus sampling
a method for obtaining cellular material from a fetus for the purpose of genetic testing
preimplantation genetic diagnosis (PGD)
a form of genetic testing in which an embryo obtained via in vitro fertilization is tested for genetic abnormalities prior to implantation within the uterus
in vitro fertilization (IVF)
in the case of humans, the fertilization of an egg outside of a female’s body
prion
an infectious particle that causes any of several types of neurodegenerative disease affecting humans or livestock; composed entirely of protein
gene therapy
the introduction of cloned genes into somatic cells or the modification of existing genes in order to treat a disease
liposome
a vesicle that is surrounded by a phospholipid bilayer
ex vivo approach
in the case of gene therapy, refers to genetic manipulations that occur outside the body
