One of the four bases in DNA that make up the letters ATGC, adenine is the “A”. The others are “G” for guanine, “C” for cytosine, and “T” for thymine. Adenine always pairs with thymine. Cytosine always pairs with guanine. These letters are used as shorthand for the sequences of fragments of DNA e.g. CCAAGTAC. These sequences are the code for genetic information.
Alternative form of a genetic locus; a single allele for each locus is inherited separately from each parent (e.g., at a locus for eye color the allele might result in blue or brown eyes).
The proportion of a particular allele among the chromosomes carried by individuals in a population.
Once all the specimens have been received at the lab, results take an average of 3-5 business days. Rush results are available upon request.
Base Pair (bp)
Two nitrogenous bases (guanine and cytosine or adenine and thymine) held together by weak bonds. Two strands of DNA are held together in the shape of a double helix by the bonds between base pairs. A set of two bonded nucleotides on opposite strands of DNA. There are two possible base pairs: C-G and A-T. These letters are used as shorthand for the sequences of fragments of DNA e.g. CCAAGTAC. These sequences are code for genetic information. Strung together in chains each base reaches across and forms a pair with its complementary base on the opposite strand. A good example would be like rungs of a ladder. Base pairing ensures that the genetic information is passed securely from generation to generation in a process called DNA replication.
The self-replicating genetic structure of cells containing the cellular DNA that bears in its nucleotide sequence the linear array of genes. Chromosomes are normally found in pairs;human beings typically have 23 pairs of chromosomes.
A branch of biological taxa or species that share features inherited from a common ancestor. A single phyletic group or line. Also cladus. Monophyletic group of taxa.
A diagram, in the form of a stylized tree, showing inferred historical branching patterns among taxa.
Constant change in a trait or trait frequency over space or time.
A diagram, in the form of a stylized tree, showing inferred historical branching patterns among taxa.
One of the four bases in DNA that make up the letters ATGC, cytosine is the “C”. The others are “A” for adenine, “G” for guanine, and “T” for thymine. Cytosine always pairs with guanine. Adenine always pairs with thymine. These letters are used as shorthand for the sequences of fragments of DNA e.g. CCAAGTAC. These sequences are the code for genetic information.
A full set of genetic material, consisting of paired chromosomes which is one chromosome from each parental set. A diploid human genome has 46 chromosomes.
DNA (deoxyribonucleic acid)
The molecule that encodes genetic information. DNA is a doublestranded molecule that is held together by weak bonds between base pairs of nucleotides. The four nucleotides in DNA contain the bases: adenine (A), guanine (G), cytosine (C), and thymine (T). In nature, base pairs form only between A and T and between G and C; thus the base sequence of each single strand can be deduced from that of its partner.
The production of many DNA copies from one or a few copies or fragments.
A term for DNA typing. There are so many millions of base pairs in each persons DNA that every person has a different sequence. However, because there are so many millions of base pairs, the task would be very time-consuming. Instead, scientists are able to use a shorter method, because of repeating patterns in DNA. These patterns do not, however, give an individual “fingerprint,” but they are able to determine whether two DNA samples are from the same person, related people, or non-related people. Scientists use a small number of sequences of DNA that are known to vary among individuals a great deal, and analyze those to get a certain probability of a match.
A gene or other fragment of DNA whose location in the genome is known.
The relative order of base pairs, whether in a gene, a chromosome, a fragment of DNA or an entire genome.
The analysis of sections of DNA for purposes of identification.
The shape that two linear strands of DNA assume when bonded together (like the rungs of a ladder).
Relating to courts or legal matters. Molecular markers are increasingly common in the context of forensics, both in wildlife and human cases involving identity or relatedness.
A segment of DNA which contains the genetic code to make a certain protein or part of a protein.
The process by which a genes coded information is converted into the structures present and operating in the cell. Expressed genes include those that are transcribed into mRNA and then translated into protein and those that are transcribed into RNA but not translated into protein.
Determination of the relative positions of genes on a DNA molecule (chromosome or plasmid) and of the distance, in linkage units or physical units, between them.
A marker is a DNA sequence with a known physical location on a chromosome. Markers can help link an inherited disease with the responsible genes. DNA segments close to each other on a chromosome tend to be inherited together. Markers are used to track the inheritance of a nearby gene that has not yet been identified but whose approximate location is known. The marker itself may be a part of a gene or may have no known function.
A collection of information about a person’s genes.
The study of the patterns of inheritance of specific traits.
All the genetic material in the chromosomes of a particular organism; its size is generally given as its total number of base pairs.
Research and technology development effort aimed at mapping and sequencing some or all of the genome of human beings and other organisms.
The genetic makeup of an organism or set of DNA variants found at one or more loci in an individual, as characterized by its physical appearance or phenotype. Our external features-what scientists call our phenotypes-are different.We have a wide array of skin color, eye shape and color, hair texture. However our interior profile, or genotype – the organization of our genes on our chromosomes-identifies us all as Homo sapiens.
One of the four bases in DNA that make up the letters ATGC, guanine is the “G”. The others are “A” for adenine, “C” for cytosine, and “T” for thymine. Guanine always pairs with cytosine. Adenine always pairs with thymine. These letters are used as shorthand for the sequences of fragments of DNA e.g. CCAAGTAC.These sequences are the code for genetic information.
Is a collection of closely related haplotypes
A single set of chromosomes (half the full set of genetic material), present in the egg and sperm cells of animals and in the egg and pollen cells of plants. Human beings have 23 chromosomes in their reproductive cells. Compare diploid.
A set of closely linked alleles (genes or DNA polymorphisms) inherited as a unit. A contraction of the phrase “haploid genotype”. Different combinations of polymorphisms are known as haplotypes.
The handing down of certain traits from parents to their offspring. The process of heredity occurs through the genes.
Having the same origin (used for genes or characters deriving from a common ancestor). Human Genome Organization (HUGO):The entity to which, among other things, scientists submit new markers for DYS number assignment.
The study of the application of computer and statistical techniques to the management of information.In genome projects, informatics includes the development of methods to search databases quickly, to analyze DNA sequence information, and to predict protein sequence and structure from DNA sequence data.
Outside a living organism.
A map of the relative positions of genetic loci on a chromosome, determined on the basis of how often the loci are inherited together. Distance is measured in centimorgans (cM).
Determination of the original position (locus) of a gene or other marker on a chromosome.
A physical location (locus) on the chromosome. Family Tree DNA offers 3 levels of Y-DNA testing: 12-marker, 25-marker and 37-marker.
Repetitive stretches of short sequences of DNA used as genetic markers to track inheritance in families. They are short sequences of nucleotides which are repeated over and over again a number of times in tandem. Changes sometimes do occur, however the number of repeats may increase or decrease.
Most recent common ancestor.
Mitochondrial DNA which is passed down from the mother to all her children, males and females.
A permanent structural alteration in DNA. In most cases, DNA changes either have no effect or cause harm, but occasionally a mutation can improve an organism’s chance of surviving, passing the beneficial change on to its descendants
A sub-unit of DNA or RNA consisting of a nitrogenous base, a phosphate molecule, and a sugar molecule. Thousands of nucleotides are linked to form a DNA or RNA molecule.
The membrane-bound organelle containing the chromosomes.
A simplified diagram of a family’s genealogy that shows family members’ relationships to each other and how a particular trait or disease has been inherited.
Our external features are called our phenotypes and are very different. We have a wide array of skin color, eye shape and color and hair texture. However our interior profile, or genotype identifies us all as human.
The evolutionary history of a species.
Polymerase Chain Reaction (PCR)
A technique allowing the production of multiple copies of extremely small amounts of DNA fragments using DNA polymerase and specific primers.
A large molecule composed of one or more chains of amino acids in a specific order; the order is determined by the base sequence of nucleotides in the gene coding for the protein. Proteins are required for the structure, function, and regulation of the body’s cells, tissues, and organs, and each protein has unique functions.
Determination of the order of nucleotides (base sequences) in a DNA or RNA molecule or the order of amino acids in a protein.
The X or Y chromosome in human beings that determines the sex of an individual. Females have two X chromosomes in diploid cells; males have an X and a Y chromosome. The sex chromosomes comprise the 23rd chromosome pair in a karyotype.
Short Tandem Repeats (STR)
Multiple copies of an identical DNA sequence arranged in direct succession in a particular region of a chromosome.
A single, distinct class of living creature with features that distinguish it from others.
Tandem Repeat Sequences
Multiple copies of the same base sequence on a chromosome; used as a marker in physical mapping.
One of the four bases in DNA that make up the letters ATGC, thymine is the “T”. The others are “A” for adenine, “G” for guanine, and “C” for cytosine. Thymine always pairs with adenine. Cytosine always pairs with guanine. These letters are used as shorthand for the sequences of fragments of DNA e.g. CCAAGTAC. These sequences are the code for genetic information.
Ways of looking, thinking, or being. Traits that are genetic are passed down from parents to offspring.
A chromosome that is different in the two sexes and involved in sex determination. The female in our species has two X chromosomes.
A chromosome that is different in the two sexes and involved in sex determination. The male in our species has one Y and one X chromosome.