G Flashcards
What is medical genetics?
The science of human biologic variation as it relates to health and disease.
What is clinical genetics concerned with?
The health of individual humans and their families.
Define a gene.
The basic physical and functional unit of heredity.
How many genes does each human cell typically contain?
30,000 genes.
What do genes instruct the body to make?
Molecules called proteins.
What is the difference between genotype and phenotype?
Genotype is the inherited genetic endowment; phenotype is the anatomical, physiological, and psychological complex of an individual.
List two components that contribute to diverse phenotypes.
- Inherited different genotypes
- Experienced different environments
What does the term ‘allele’ refer to?
Two or more alternative forms of a gene found at the same place on homologous chromosomes.
What distinguishes a dominant allele from a recessive allele?
One allele is enough to express its phenotype (dominant); both alleles are needed to express the phenotype (recessive).
What is a pedigree diagram?
A pattern of allele distribution among members of a family.
What are monogenic disorders?
Genetic disorders arising from mutation in one gene.
What percentage of early morbidity and mortality is attributed to monogenic disorders?
10%.
What is a karyotype?
An individual’s collection of chromosomes.
What percentage of childhood deaths is attributed to chromosomal defects?
About 2.5%.
What are multifactorial traits?
Traits due to the combined action of several genes (polygenic) as well as environmental factors.
What is cytogenetics?
The study of chromosomes.
What does immunogenetics study?
Unique rearrangements of genetic material associated with maturation of the immune system.
What is pharmacogenetics?
The study of differential responses to unusual biochemical, guiding prescription dosages.
Who is known as the father of genetics?
Gregor Mendel.
What are Mendel’s four principles of inheritance?
- Unit inheritance
- Dominance
- Segregation
- Independent assortment
Define wildtype.
An individual with a normal allele generally found in a natural population.
What is meant by homozygous?
Individuals with identical alleles.
What does the principle of dominance state?
The effects of one allele can be masked by those of a dominant partner allele.
What occurs during gamete formation according to the principle of segregation?
Alleles of a pair separate and each enter a separate cell.
True or False: The alleles of different genes assort independently of one another.
True.
What is gene therapy?
Gene technologies to cure or prevent diseases.
Fill in the blank: The term ‘inborn errors of metabolism’ describes _______.
Inherited physiological disorders.
