What is DNA sequencing?

DNA sequencing is the process of determining the exact order of nucleotide bases (A, T, G, C) in a DNA molecule — modern methods can sequence billions of bases in a single day DNA sequencing is the process of cutting DNA into pieces for use in genetic engineering DNA sequencing determines which genes are active in a cell at a given moment DNA sequencing is only used in forensic science to identify criminals

What was the Human Genome Project and what did it achieve?

The Human Genome Project (1990-2003) was an international collaboration that sequenced the entire human genome — all 3.2 billion base pairs — creating a reference map used in medicine, research, and biotechnology The Human Genome Project was a program to create genetically modified humans with enhanced abilities The Human Genome Project mapped the location of every gene but did not sequence the DNA The Human Genome Project was a US government program to store every person's DNA in a national database

What is a genome?

A genome is the complete set of genetic information in an organism — in humans, this includes all 46 chromosomes with their 3.2 billion base pairs of DNA A genome is a single chromosome containing all of an organism's genes A genome is the set of genes that an organism expresses — genes that are switched off are not part of the genome A genome is a database of all known genetic mutations associated with disease

What is a SNP (single nucleotide polymorphism)?

A SNP is a position in the genome where a single base differs between individuals — there are about 4-5 million SNPs between any two unrelated people, and they are used to study disease risk, ancestry, and evolution A SNP is a type of mutation that always causes disease SNPs are large chromosomal rearrangements that cause chromosomes to swap segments A SNP is a specific gene sequence found only in humans and not in other primates

What is genetic testing and what can it reveal?

Genetic testing analyzes DNA to identify mutations, variants, or chromosomal changes — it can diagnose genetic conditions, reveal carrier status, predict disease risk, determine ancestry, and guide treatment choices Genetic testing can only determine if someone will definitely develop a genetic disease — it cannot estimate risk Genetic testing is only used in criminal investigations to identify suspects Genetic testing alters DNA to fix mutations found in the test

What is the BRCA1/BRCA2 gene story and why is it clinically important?

BRCA1 and BRCA2 are tumor-suppressor genes — certain mutations in these genes greatly increase the risk of breast and ovarian cancer, and carriers can take preventive action including increased surveillance or prophylactic surgery BRCA1 and BRCA2 are cancer-causing genes — carrying them means you will definitely develop cancer BRCA1 and BRCA2 mutations only affect females — males cannot carry or transmit these mutations BRCA1 and BRCA2 are related to bacteria and cause breast infections, not cancer

What is comparative genomics?

Comparative genomics compares the genomes of different species to identify conserved sequences, understand gene function, and trace evolutionary relationships Comparative genomics compares the genomes of different individuals within a species to identify disease variants Comparative genomics is the study of how genomes change during an individual's lifetime Comparative genomics only compares human genomes to determine ancestry

What is DNA fingerprinting and how does it work?

DNA fingerprinting identifies individuals by analyzing short tandem repeats (STRs) — regions where short DNA sequences repeat a variable number of times — producing a unique profile that can be used for forensics, paternity testing, and identifying remains DNA fingerprinting creates a copy of a person's entire genome to use as identification DNA fingerprinting uses the actual fingerprint ridges on a finger to extract DNA DNA fingerprinting identifies people by comparing the shapes of their DNA molecules under a microscope

What is ancient DNA analysis and what has it revealed?

Ancient DNA is extracted from preserved remains (bones, teeth, permafrost specimens) and sequenced — it has revealed interbreeding between modern humans and Neanderthals and the migration routes of ancient human populations Ancient DNA can only be extracted from Egyptian mummies because other remains are too degraded Ancient DNA studies have proven that modern humans evolved independently on every continent Ancient DNA is identical to modern human DNA — no changes have occurred in human genes over thousands of years

What is population genetics?

Population genetics studies the frequency and distribution of genetic variants in populations over time — it explains how mutation, natural selection, genetic drift, and gene flow change the genetic makeup of populations Population genetics studies the genetics of endangered species only Population genetics examines how the number of genes in a species changes over evolutionary time Population genetics is the study of how populations respond to genetic diseases