Module 9 slides

PCR

Polymerase Chain Reaction for DNA amplification.

Electrophoresis

Technique to separate DNA by size.

STR

Short Tandem Repeats, useful in forensics and DNA profiling

VNTR

Variable Number of Tandem Repeats in DNA.

Kary Mullis

Developer of the PCR protocol.

Denaturation

Heating DNA to 95°C to separate strands.

Annealing

Primers bind to DNA at 50-65°C.

Taq polymerase

Enzyme that adds nucleotides during PCR.

Polymorphic loci

Regions with multiple alleles for identification.

Amplification limit

PCR typically amplifies up to 2000 bp.

Contamination risk

PCR susceptible to lab DNA contamination.

Error rate

Taq polymerase has 1 in 20,000 bp errors.

Gel wells

Holes in gel for DNA sample placement.

Negative pole

Electrophoresis end where DNA is loaded.

Positive pole

Electrophoresis end where DNA migrates.

Paternity testing

Determining fatherhood using DNA analysis.

Allele length

Length variations in DNA segments define alleles.

Perfect match

Exact allele match indicates potential identity.

Exclusion criteria

Rules out suspects based on DNA mismatch.

Microsatellite regions

Short repeating sequences in DNA.

Practice problem

Exercise to determine possible fathers using STRs.

Ethical issues related to forensic testing

Concerns surrounding forensic DNA testing practices.

CODIS

Combined DNA Index System for forensic identification.

Innocence Project

Organization that exonerates wrongfully convicted individuals.

Familial DNA Searching

Identifying relatives of DNA profiles in databases.

Ethical Issues in DNA Testing

Concerns about privacy versus crime-solving effectiveness.

Polymorphic Characteristic

Variability in DNA regions among individuals.

Product Rule

Probability calculation for independent genetic loci.

DNA Database

Collection of DNA profiles for law enforcement.

Capillary Electrophoresis

Technique for separating DNA fragments by size. Uses narrow bone capillary tube instead of gel

STR Assay

Test amplifying multiple STR loci simultaneously.

Partial Match Data

Using incomplete DNA profiles for investigations.

Ethical Conflict in DNA Testing

Balancing crime resolution and individual privacy rights.

SNP

Single Nucleotide Polymorphism, a genetic variation.

Gene Chips

Microarrays for identifying patient genotypes.

Ecogenetics

Study of genetic variation affecting chemical responses.

Safety/ guideline Standards in Genomics

Guidelines for diverse genetic backgrounds in medicine.

GINA defintion

Genetic Information Nondiscrimination Act protecting genetic data.

Loci

Specific locations on chromosomes for genetic markers.

Alleles

Different forms of a gene at a locus.

DNA Sampling Warrant

Legal requirement for collecting DNA samples.

Genetic Testing Importance for helping with

Crucial for personalized medicine and health assessments.

Crime Scene DNA

DNA collected from locations of criminal activity.

DNA Profile Hits

Matches found between DNA profiles in databases.

SNPs

Single Nucleotide Polymorphisms, genetic variations at one base.

Haplotype

A sequence of SNP patterns on a chromosome.

tagSNPs

Few SNPs identifying a larger haplotype.

SNP density

100,000 SNPs can identify most human haplotypes.

Gene Chip

Microarray technology for SNP detection.

SNP probes

Short DNA sequences on a chip for matching.

Association Studies

Correlate SNP presence with genetic disorders.

Correlation vs. Causation

Correlation does not imply direct cause.

risk of exposure to a chemical depends on the genetics involved in

transport of chemicals influenced by genetics, metabolism of the chemical, and excretion of the chemical

parathion

common pesticide is broken down into a toxic chemical paraoxan.

Paraoxonase

Enzyme detoxifying paraoxan from pesticides.

RR genotype for paraoxan

Detoxifies paraoxan 10 times faster than QQ. Since RR is dominant.

Pesticide Sensitivity

Varied responses to pesticides based on genetics.

Genotype Frequency

Distribution of genotypes within a population.

African Americans QQ frequency for pesticides

Approximately 10% have QQ genotype.

Latino Americans QQ frequency for pesticides

Approximately 35% have QQ genotype.

Caucasian Americans QQ frequency for pesticides

Approximately 47% have QQ genotype.

Safety Testing Implications

Genetic differences affect safety testing outcomes.

Drug Sensitivity

Variability in drug metabolism among individuals.

Suxamethonium

Short-acting muscle relaxant; recovery varies by genetics.

Autosomal Recessive Condition

Requires two copies of mutated gene to express.

Precision Medicine Initiative

2015 effort to personalize medical treatment based on genetics.

Patient Privacy

Confidentiality of patient data in medical research.

Tamoxifen

Breast cancer drug reducing recurrence and mortality.

CYP2D6 Gene

Gene affecting tamoxifen metabolism rates.

Tamoxifen Metabolism

Varies among women, influencing treatment effectiveness.

Alleles and drug use

Different forms of a gene, affecting drug metabolism.

Phenotypes

Observable characteristics resulting from genetic variations.

Warfarin

Blood thinner with significant dose variability.

CYP2C9 Gene

Gene encoding enzyme for warfarin metabolism.

VKORC1 Gene

Gene influencing warfarin's therapeutic dose.

Direct to Consumer Testing

Genetic tests marketed directly to consumers and how Genetic tests available without physician involvement.

SNP Probes

Used to identify genetic variations in testing.

Ancestry.com and 23 and Me

DTC testing service costing approximately $99.

DTC testing for ancestry and limited health info.

Genotype

Individual's genetic makeup influencing treatment response.

Informed Consent

Patient's agreement after understanding risks and benefits to test outcomes.

Healthcare Provider Education

Training necessary for understanding precision medicine.

Data Analysis Tools

Developed for managing large medical datasets.

FDA Oversight

Regulation ensuring safety of drugs and tests.

Recurrence Risk

Increased likelihood of cancer returning post-treatment.

SNP Patterns

Common genetic variations in specific populations.

BRCA1 Mutation

A genetic alteration increasing cancer risk.

Ethical Questions in Genomics (genetic info)

Concerns about genetic information usage and access.

GINA

Protects against genetic discrimination in health insurance.

GINA Provisions

Insurance cannot alter coverage based on genetic tests.

GINA Employment Protections

Employers cannot discriminate based on genetic test results.

Genetic Testing Requirements

No mandatory genetic testing by insurers or employers.

Racial Disparities in DNA Databases

Concerns about bias in genetic data collection.

Genetic Counseling

Support for understanding genetic diseases and risks.

Genetic Counselor Responsibilities/ role. what do they do

Gathering medical histories and assessing genetic risks.

Patient Education

Informing patients about disorders and inheritance patterns.

Informed Decision Making

Empowering patients to make choices about their care.

Non-Directive Counseling

Counselors provide options without imposing decisions.

Psychological Support

Emotional assistance during genetic counseling sessions.

Screening Test

Identifies potential genetic disorders in asymptomatic individuals. estimates risk of genetic disorder.

Diagnostic Test

Confirms the presence of a genetic disorder.