Introduction to Molecular Biology and Genetics

genetics

the study of heredity; the roles and functions of single genes and varients

genomics

study of whole organism genomes: sequence, genetic mapping, interactions between loci and alleles within the genome

pharmacogenetics

use of genetic data to inform drug development and testing; correlate individual genetic variation with drug responses

law of segregation (first law)

every individual has two alleles for any particular trait and each parent passes a randomly selected copy of only one allele to its offspring

law of independent assortment (second law)

separate genes for separate traits are passed independently of one another (exception: linked genes)

autosomal recessive

genetic disorders characterized by the presence of two mutated alleles (ex: CF, sickle cell anemia); individuals only have disorder if they poses the two abnormal (recessive) alleles

X-linked

genes carried on the X chromosome; females can be carriers but males will always have the phenotype if they have the gene

genome

the entire DNA content; almost every cell contains an entire copy

3 billion

the human genome is _________________ nucleotides

gene

unit of heredity passed from generation to generation; segments of DNA that code for particular proteins

2%

only _________ of our genome consists of genes

diploid

having two sets of chromosomes; genes occur in pairs in autosomes

haploid

having one set of chromosomes; alleles separate randomly in gametogenesis

aneuploidy

Abnormal number of chromosomes.

locus

position on chromosome where particular gene is; can be occupied by any one of the alleles of a gene

allele

one variant form of a gene at a particular locus

autosomes

all chromosomes except sex chromosomes

sex chromosomes

chromosomes X and Y

genotype

internally coded heritable information or genetic constitution of an individual - combination of alleles at a given locus

phenotype

observable manifestation of a gene

haplotype

genotype of a group of alleles from two or more closely linked loci on one chromosome; usually inherited as unit

mutation

any permeant heritable change in the genome sequence

polymorphism

variations that occur in greater than 1% of the population (10x more frequent than regular mutation)

genetic polymorphism

condition in which one of the two different but normal nucleotide sequences can exist at a particular site in DNA

homozygous

have two identical alleles at a given locus

heterozygous

have different alleles at given locus

molecular biology

study of gene structure and its coded proteins function

central dogma

DNA --(transcription)--> RNA --(translation)--> Protein