Bio ch 20 pt 1

Recombinant DNA

Combining DNA from 2 sources into a novel molecule

Cloning

Producing identical DNA clones by replication and division

Restriction Enzymes

Enzymes cutting DNA at specific sites

Plasmids

Circular DNAs replicating autonomously

Gel Electrophoresis

Separating DNA fragments based on size using a gel matrix

Transformation

Bacteria taking up DNA from surroundings

Genomic Library

Collection of DNA fragments representing an entire genome

cDNA Library

Collection of DNA fragments representing expressed sequences

Hybridization

Finding DNA sequences by complementary base-pairing

Echo R1

First identified restriction enzyme from E. coli

Agarose Gel

Polymer gel used in electrophoresis to separate DNA fragments

Ligase

Enzyme joining DNA fragments by forming phosphodiester bonds

Molecular Scissors

Nickname for restriction enzymes due to DNA cutting ability

Sticky Ends

Single-stranded DNA overhangs allowing DNA molecules to stick together

Selectable Marker

Gene providing resistance to specific antibiotics in plasmids

Multiple Cloning Site

Region in plasmids with unique restriction sites for gene insertion

Complementary DNA (cDNA)

DNA synthesized from mRNA templates to represent expressed sequences

Origin of Replication

Site where DNA replication begins in plasmids

Palindromes

Sequences that read the same forwards and backwards

Recombinant Molecules

DNA molecules formed by combining fragments with compatible ends

UV Light

Light used to visualize DNA fragments in gel electrophoresis

Endonucleases

Enzymes cutting DNA internally at specific sites

Antibiotic Resistance

Ability of bacteria to resist the effects of antibiotics

Messenger RNA (mRNA)

RNA molecules carrying genetic information from DNA to ribosomes

Phosphodiester Bonds

Chemical bonds linking nucleotides in DNA and RNA

Denature

Breaking hydrogen bonds in DNA strands with heat

Renature

Reforming hydrogen bonds in DNA strands after cooling

Library screening

Identifying clones containing a specific gene

In situ hybridization

Hybridization done within an organism

Polymerase Chain Reaction (PCR)

Technique to amplify DNA segments in vitro

Thermocycler

Machine cycling through temperatures for PCR

Primers

Short DNA sequences initiating DNA synthesis

Taq polymerase

Heat-stable enzyme used in PCR

CODIS

Combined DNA Index System for profiling

SNP

Single nucleotide polymorphism variant

STR

Short tandem repeat variant in DNA

Heterozygous

Having different alleles at a genetic locus

Capillary tube gel electrophoresis

Separating DNA fragments based on size in a gel

Fluorescent tag labeling

Tagging DNA fragments for visualization

Base pair count

Number of base pairs in a DNA segment

Relatedness analysis

Determining genetic relationships between samples

Automated detection

Using laser and detector to measure DNA fragments

PCR product amplification

Increasing DNA copies using primers

Exponential amplification

Doubling DNA copies with each PCR cycle

Forensics application

Using DNA analysis for legal investigations

Identity determination

Establishing if DNA samples are from the same person

Polymorphic loci

Genetic sites with multiple forms in the genome

Variability source

Regions causing genetic differences between individuals

Genetic relatedness

Determining genetic connections between individuals

Innocence Project

Nonprofit using STR analysis to revisit old legal cases

Genetic Profiles

Accepted as compelling evidence by legal experts

Paternity Testing

Using genetic profiles to determine biological father

Mass Casualty Identification

Using genetic profiles to identify victims

PCR Cycle Steps

1. Denaturation 2. Annealing 3. Extension

Automated DNA Sequencing

Evolution from 1st to 3rd generation for efficiency

Genomics

Study of all genes in an organism and their functions

Genome Sequencing Advancements

Increased speed, decreased cost for sequencing

Genome Structure

Includes size, gene number, and gene density

Gene Density

Number of genes per unit length of DNA

Introns

Non-coding DNA within genes

Exons

Coding sequences in genes

Comparative Genomics

Studying evolutionary relationships using DNA sequences

Sequence Alignment

Matching DNA sequences to identify similarities

Molecular Clock

Estimating time since species divergence

Chromosome Fusion

Two ancestral chromosomes fused in human evolution

Human-Chimp Genetic Differences

1.2% at single base pairs, 2.7% due to insertions/deletions

HARs

Human accelerated regions, genes evolving faster in humans

Genomic Sequences

DNA sequences undergoing evolutionary changes over time

Selective Advantage

Beneficial mutation spreading rapidly in a population

Gene Regulation

Controlling gene expression through switches turning nearby genes on/off

Embryological Development

Changes during embryo growth affecting species differences

Enhancer

Region regulating gene expression, like HAR-2 in wrist development

Zoonomia Project

Comparing mammalian species sequences, studying genetic variations

hsSV

Human specific structural variant altering genome folding

Chromatin

Complex of DNA and proteins, impacting gene regulation

Enhancer Hijacking

Non-random insertion changing gene regulation, a mechanism of evolution

FOXP2 Gene

Gene encoding a transcription factor for vocalization

Functional Genomics

Study of gene function across species, using model organisms

Model Organisms

Cost-effective systems for studying gene function, like mice and fruit flies

Knockout Mouse

Mouse model with disrupted gene to study gene function

Genetic Disorder

Condition caused by abnormal gene function or mutation

Phenotype

Observable traits resulting from gene expression or mutation

Bacterial Species Genome

Approximation of genome size in Mb and number of genes

Genome Complexity

Factors affecting organism complexity beyond gene count

Alternative Splicing

Process increasing polypeptide diversity from a single pre-mRNA

Post-Translational Modifications

Changes after protein synthesis, expanding protein types