Glossary: First 20 Words
On February 24, 2020 the Foundation for Cell & Gene Medicine convened Speaking of Genes with a group of stakeholders in Washington, DC, hand-selected for their roles and knowledge of genetic nomenclature. The group has identified terminology and definitions used in messaging about cell & gene medicine for the general public.
The purpose of this glossary is to reconcile for patients, caregivers and families the numerous definitions for complex ideas pertinent to understanding Cell & Gene Medicine. The purpose is not to teach molecular biology, but to build off what people already know, clarify the meaning of words you might hear, and aid the ability to understand what you hear, read, and discuss with friends and families.
Here are the FIRST 20 terms in the Speaking of Genes Glossary 2020.
AAV
Adeno-associated viruses (AAV) are small viruses that can be deactivated and used to transmit gene-based treatments to patients.
Allele
One of several possible versions of a gene. Each allele contains a distinct variation in its DNA sequence.
In human bodies, genes come in pairs. Each member of the pair is called an allele, and each allele contains a distinct DNA sequence. Some human genes have many allele variants, others have only a few. Located at specific positions on a chromosome, the interactions between alleles lead to distinctive traits. Some alleles contain mutations that could cause diseases. Alleles can be dominant or recessive.
Allogeneic
Allogenic refers to the transfer of tissue or cells from one person to another for the treatment of disease, to restore the immune system, or to help repair an injury.
Autologous
Autologous refers to therapies that use tissue or cells from a patient to treat the patient’s disease or help repair an injury.
Capsid
The outside shell that protects a virus and helps it penetrate a cell membrane. A capsid is a protein coat that surrounds a virus. A capsid protects the contents, and helps the virus attach to a targeted cell to penetrate the cell membrane. In gene editing, the special characteristics of a capsid can enable gene delivery to specific cells.
Cell Therapy
Cell therapy is the transfer of whole cells into a patient to replace or repair damaged tissue or cells. A bone marrow transplant is the most frequently used cell therapy.
CRISPR
CRISPR is a gene-editing technique that allows scientists to alter DNA sequences easily and precisely in order to modify gene function. CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats that are a type of DNA sequence in a gene. This type of DNA sequence is understood by scientists who can use molecular tools to modify how the gene functions.
Chromosome
A chromosome is a structure, located in the nucleus of a cell, that contains DNA. Genes are located in the chromosomes.
A person typically has 46 chromosomes, inheriting half (23) of those chromosomes from each parent. Chromosomes are found in the cell’s command center, the nucleus.
Ex Vivo Gene Therapy
Gene therapy that is delivered to cells outside a patient’s body and then transferred back into the patient.
“Ex vivo” means from outside the body. Ex-vivo gene therapy is a therapeutic technique where some of the patient’s cells are collected, genetically modified outside the body, and then delivered back into the patient for the treatment of disease.
Gene Editing
Gene editing makes targeted changes to existing DNA in genes located on the chromosomes. With gene editing, researchers can enable or disable targeted genes, correct harmful mutations, and change the activity of specific genes.
Gene editing is a set of techniques that enable researchers and clinicians to rewrite the instruction encoded in the DNA of genes. These molecular-biology techniques can enable or disable targeted genes, correct harmful mutations, modify expression of genes or change activity of a specific cell, with the goal of restoring normal function. CRISPR is an example of a gene editing technique.
Gene Modified Cell Therapy
A therapeutic approach in which a person’s cells are genetically modified in order to help the patient fight a disease. Therapies created this way can also be called Ex Vivo gene therapies.
A therapeutic approach in which a person’s cells are modified outside the body, genetically recoded and enhanced. These cells then returned to the patient in order to help the patient fight a disease, for example, in CAR T-cell therapy for cancers.
Gene Therapy
Gene therapy is a technique that modifies a person’s genes to treat or cure disease. Human gene therapy seeks to modify or manipulate the expression of a gene or to alter the biological properties of living cells for therapeutic use.
Gene therapies can work by several mechanisms
- Replacing a disease-causing gene with a healthy copy of the gene
- Inactivating a disease-causing gene that is not functioning properly
- Introducing a new or modified gene into the body to help treat a disease
Gene therapy products are being studied to treat diseases including cancer, genetic diseases, and infectious diseases.
Genes
Regions of DNA that direct the production of proteins that are the building blocks of our bodies. Genes are inherited from our biological parents. Defective genes can result in a disease or medical disorder.
Genes direct biologically important functions throughout the body. Mutations, or errors, in genes can cause disease by failing to produce sufficient levels of a functional protein.
Gene Editing
Gene editing makes targeted changes to existing DNA in genes located on the chromosomes. With gene editing, researchers can enable or disable targeted genes, correct harmful mutations, and change the activity of specific genes.
Gene editing is a set of techniques that enable researchers and clinicians to rewrite the instruction encoded in the DNA of genes. These molecular-biology techniques can enable or disable targeted genes, correct harmful mutations, modify expression of genes or change activity of a specific cell, with the goal of restoring normal function. CRISPR is an example of a gene editing technique that has entered clinical trials.
Gene Modified Cell Therapy
A therapeutic approach in which a person’s cells are genetically modified in order to help the patient fight a disease. Therapies created this way can also be called Ex Vivo gene therapies.
A therapeutic approach in which a person’s cells are modified outside the body, genetically recoded and enhanced. These cells then returned to the patient in order to help the patient fight a disease, for example, in CAR T-cell therapy for cancers.
Gene Therapy
Gene therapy is a technique that modifies a person’s genes to treat or cure disease. Human gene therapy seeks to modify or manipulate the expression of a gene or to alter the biological properties of living cells for therapeutic use.
Gene therapies can work by several mechanisms
- Replacing a disease-causing gene with a healthy copy of the gene
- Inactivating a disease-causing gene that is not functioning properly
- Introducing a new or modified gene into the body to help treat a disease
Gene therapy products are being studied to treat diseases including cancer, genetic diseases, and infectious diseases.
In Vivo Gene Therapy
Gene therapy that modifies cells inside a patient’s body.
“In vivo” means within the living body. “In vivo” gene therapies place gene-modifying therapy directly inside the patient’s body.
Lentivirus Vector
Lentivirus vectors use parts of a lentivirus that are made harmless. The vector can carry genetic information into the nucleus of cells, potentially allowing for stable and durable expression of the genetic information that it integrated into the cells.
One of the many vector types used by gene therapy researchers are lentiviral vectors. This vector can integrate its genome into both dividing and non-dividing cells in the body, leading to new gene expression that is designed to be stable and durable.
Regenerative Medicine
A field of medicine that aims to improve, replace, or repair cells, tissues, genes or organs.
Doctors use cell therapies, gene therapies, and tissue-engineered products to replace or regrow human cells, genes, tissues or organs. This field holds the promise of repairing damaged tissues and organs and restoring function lost due to age, disease, damage, or birth defect.
Somatic Cells
Somatic cells are any cells in the body except sperm and egg cells. Changes made to the DNA in a somatic cell will not be inherited by a patient’s future children.
Stem Cells
Stem cells distinguish themselves from other cell types by two unique characteristics. One, they are unspecialized cells capable of renewing themselves through cell division. When a stem cell divides, each new cell has the potential to remain a stem cell or become another more specialized cell type like a red blood cell or a muscle cell. Two, a stem cell can be induced to become tissue or organ specific stem cells with specific functions. This makes them useful in medical treatments.
The most commonly used stem cell treatment is hematopoietic (blood) stem cell transplantation, for example, bone marrow transplantation, to treat certain blood and immune system disorders or to rebuild the blood system after treatments for some kinds of cancer.
Given their unique regenerative abilities, stem cells offer new potential for treating disease but not all stem cell treatments have been proven to be effective and should be considered experimental.
Tropism
The ability of different vectors to target specific cell types or tissues.
A tropism is the natural attraction of a virus or vector to receptors present only on certain cells or tissues. Gene therapy researchers exploit tropisms to help different viruses, lipid particles, or other therapeutic carriers reach their targeted cells.
Vectors
Delivery vehicles, or carriers, that encapsulate therapeutic genes for delivery to cells. These include both disabled viruses and nonviral vectors, such as lipid particles.
Next 20 Words for Review
Below are the possible candidates for the SECOND 20 nomenclature definitions:
Antibody
Clinical Trial
Cure
Deletion
DNA
Durability
Embryonic stem cells
Enzyme
Gene expression
Gene testing
Genetic marker
Genome, genomics, whole genome sequencing
HSC – Hematopoietic stem cell
Mutation
Newborn screening
Off target
Personalized medicine
Precision medicine
Protein
Redosing (gene therapy)
RNA – differences between DNA and RNA
Variance