Gene Expression and Genetic Disorders Lecture Notes

This set of flashcards encompasses key vocabulary and concepts related to gene expression, genetic mutations, genetic disorders, and biotechnological techniques.

MicroRNAs (miRNAs)

Small non-coding RNA molecules that regulate gene expression by binding to mRNA.

Polycistronic mRNA

mRNA that codes for more than one protein, typically found in prokaryotes.

Monocistronic mRNA

mRNA that codes for a single protein, typically found in eukaryotes.

Operon

A cluster of functionally related genes under the control of a single promoter, found in prokaryotes.

Trp Operon

A repressible operon that is active in the absence of tryptophan.

Lac Operon

An inducible operon that is expressed in the presence of lactose.

Enhancers

Short regions of DNA that bind proteins to promote the expression of genes.

Promoters

Regions of DNA that initiate transcription by binding RNA polymerase.

TATA Box

A DNA sequence that binds transcription factors to regulate gene expression.

Transcriptional Start Site

The location within the promoter where transcription begins.

Open Reading Frame (ORF)

The part of a gene that codes for a protein, starting with an ATG and ending with a stop codon.

Genetic Mosaicism

Presence of two or more different populations of cells with different genotypes in one organism.

Chimerism

Fusion of more than one fertilized zygote early in development, resulting in an organism with cells from different zygotes.

Mutagenesis

The process of making mutations, often induced by radiation or chemicals.

Forward Genetics

Approach where mutations are randomly made and screened for desired phenotypes.

Reverse Genetics

Method to identify the phenotype resulting from a specific gene mutation.

Erameshift mutation

Mutation resulting from addition or deletion of nucleotides, shifting the reading frame of the gene.

Nonsense mutation

A mutation that creates a premature stop codon in the protein sequence.

Trinucleotide Repeats

Repeats of a short sequence of three nucleotides in a gene associated with genetic disorders.

Defective Genes

Genes that do not produce the correct protein, potentially resulting in genetic disorders.

Nondisjunction

Failure of chromatids to separate properly during meiosis, leading to gametes with abnormal chromosome number.

X-linked Recessive Disorders

Genetic disorders that occur when a defective gene is located on the X chromosome.

Sanger Sequencing

A method for determining the nucleotide sequence of DNA using labeled chained-terminating nucleotides.

CRISPR-Cas9

A genome editing technology that uses a guide RNA and Cas9 enzyme to modify DNA sequences.

Gene therapy

An experimental technique that uses genes to treat or prevent diseases.

Bioethics

Field of study that addresses the ethical implications of biological research and applications.

Epigenetics

Study of heritable changes in gene expression that do not involve changes to the underlying DNA sequence.