This glossary explains abbreviations and acronyms that come up in medical appointments, school meetings, benefit applications, and research -- all in one place. It covers terms from across the site. For definitions of full medical and genetic terms (not just abbreviations), see the Medical Terms Guide.
Not a substitute for guidance from your care team, school team, or benefits specialist.
A
Devices, apps, boards, or systems that supplement or replace spoken speech for people who have difficulty communicating verbally. Includes picture boards, speech-generating devices (SGDs), and apps like Proloquo2Go.
A therapy approach based on understanding and modifying behavior through structured learning techniques. Widely used in autism and developmental disability support. Can be delivered in school, clinic, or home settings.
A federal law that created tax-advantaged savings accounts (ABLE accounts) for people with disabilities. Money saved in an ABLE account does not count against SSI or Medicaid asset limits. Eligible uses include housing, education, transportation, and assistive technology.
A federal civil rights law that prohibits discrimination against people with disabilities in employment, public services, and places of public accommodation. Relevant to school transition planning, workplace accommodations, and access to public programs.
A neurodevelopmental condition characterized by inattention, impulsivity, and/or hyperactivity that interferes with daily functioning. Diagnosed by a psychologist, psychiatrist, or developmental pediatrician.
A neurodevelopmental condition affecting social communication, interaction, and behavior, often accompanied by restricted or repetitive patterns. Diagnosed through standardized evaluation. A broad spectrum with widely varying presentations.
An informal term used in neurodiversity communities to describe an individual who has both Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD). Not a standalone clinical diagnosis; a person receives separate ASD and ADHD diagnoses. The term reflects the significant overlap in how these two conditions can present and interact.
B
A written plan, developed with school staff, that identifies specific behaviors of concern and outlines strategies to address them. A BIP is developed from the results of a Functional Behavioral Assessment (FBA) and becomes part of the student’s IEP.
C
A structural problem with the heart present from birth. Types vary widely in severity, from minor defects that close on their own to complex issues requiring surgery. Evaluated by a pediatric cardiologist.
A federal-state program that provides low-cost health insurance to children in families who earn too much for Medicaid but cannot afford private insurance. Eligibility rules vary by state.
A genetic test that looks for extra or missing pieces of chromosomes (copy number variants) across the entire genome. CMA can detect large deletions and duplications but does not identify single-letter changes in individual genes like the variants that cause SETD5 Syndrome.
An imaging test that uses X-rays from multiple angles to create cross-sectional pictures of internal structures. Often used in urgent or emergency settings. For detailed brain imaging, MRI is generally preferred.
D
A significant lag in one or more areas of development (motor, language, cognitive, social/emotional, adaptive) compared to same-age peers. “Global developmental delay” (GDD) refers to delays in two or more domains. Often used for children under age 5; in older children, a more specific diagnosis may be given after evaluation.
A state-level agency (name varies by state) that provides services and supports to people with intellectual and developmental disabilities, including residential support, day programs, and community inclusion services. Often has long waitlists -- early enrollment may reduce wait time for services.
A score used in early childhood to describe overall development relative to age norms, similar to an IQ score but used for very young children before formal IQ testing is reliable. Produced by developmental assessments like the Bayley Scales or Griffiths.
A Social Security benefit available to some adults whose qualifying disability began before age 22. May be available when a parent receives Social Security retirement or disability benefits, or has passed away after qualifying for Social Security. Benefit amounts are based on the parent's work record. DAC benefits may provide a higher monthly payment than SSI in some cases, depending on the parent's work record. Families may want to discuss DAC eligibility with a benefits counselor.
E
A test that records the electrical activity of the heart. Used to detect arrhythmias, structural heart problems, and other cardiac conditions. ECG is the internationally preferred abbreviation; EKG comes from the German spelling (Elektrokardiogramm). They refer to the same test.
A test that records electrical activity in the brain using electrodes placed on the scalp. Used to evaluate seizures and epilepsy, as well as other neurological conditions. Can be performed as a routine test, a sleep-deprived test, or a long-term ambulatory (wearable) recording.
A federally mandated program under Part C of IDEA that provides developmental services to infants and toddlers (birth to age 3) with disabilities or developmental delays. Services are delivered in the home or community and are guided by an Individualized Family Service Plan (IFSP). Families can self-refer by contacting their state's Early Intervention program. Children with a diagnosed condition such as SETD5-related disorder may qualify based on the diagnosis itself or through developmental evaluation.
Special education services provided beyond the standard school year (typically during summer) for students who would otherwise experience significant regression in skills. ESY eligibility must be determined individually by the IEP team -- it is a right under IDEA for qualifying students, not an add-on service parents must pay for.
F
A right guaranteed under IDEA (the Individuals with Disabilities Education Act). Every eligible student with a disability is entitled to receive special education and related services at no cost to the family, designed to meet their individual needs.
An assessment process that identifies the reasons behind a student’s challenging behavior -- what triggers it, what reinforces it, and what function it serves for the student. Used to develop an effective Behavior Intervention Plan (BIP). Parents can request an FBA as part of the IEP process.
A targeted genetic test that uses fluorescent probes to detect specific chromosomal regions or genes. FISH can identify deletions or duplications at a specific known location, but unlike CMA, it only looks where it is directed. Not commonly used for initial SETD5 Syndrome diagnosis.
A federal law that allows eligible employees to take up to 12 weeks of unpaid, job-protected leave per year to care for a family member with a serious health condition. Some states offer expanded or paid versions of family leave. Relevant for parents attending frequent medical appointments or during hospitalizations.
The U.S. federal agency responsible for approving medications, medical devices, and other health products. FDA approval means a treatment has been reviewed for safety and efficacy for a specific use. For rare conditions, FDA may grant “orphan drug designation” to encourage development of treatments.
G
A condition where stomach acid regularly backs up into the esophagus, causing discomfort, vomiting, or feeding difficulties. Gastroesophageal reflux (GER without the “D”) refers to normal, less frequent reflux; GERD indicates it is chronic or causing problems.
Relating to the digestive system, from the mouth to the bowel. A “GI specialist” is a gastroenterologist. GI issues can include reflux, constipation, feeding difficulties, and bowel motility problems.
H
A category of Medicaid-funded services that support people with disabilities living in their homes and communities, rather than in institutional settings. Includes personal care assistance, respite care, supported employment, and day programs. Delivered through state waiver programs, which vary significantly.
I
A condition characterized by significant limitations in both intellectual functioning (reasoning, learning, problem solving) and adaptive behavior (everyday social and practical skills), originating before age 18. Previously called “mental retardation” -- that terminology is no longer used. Severity is described as mild, moderate, severe, or profound.
The primary federal law governing special education in the United States. IDEA guarantees students with disabilities the right to a free appropriate public education (FAPE) in the least restrictive environment (LRE). It also governs the IEP process and parental rights throughout.
A legally binding document that describes a student’s current abilities, annual goals, and the specific special education services, supports, and accommodations the school will provide. Created collaboratively by parents and the school team. Reviewed at least annually; parents can request a meeting at any time.
The early childhood equivalent of an IEP, used for children in Early Intervention (birth to age 3) under IDEA Part C. An IFSP documents a child's current development, family priorities, and the services to be provided. It is developed collaboratively with the family and reviewed every six months. When a child turns 3, services transition from the IFSP to a school-based IEP.
A score derived from standardized tests that estimate cognitive ability. The average IQ is set at 100. IQ scores are one component of diagnosing intellectual disability, but they do not capture the full picture of a person’s abilities or potential.
A committee that reviews and approves research involving human participants to ensure ethical standards are met. If your family participates in a research study, an IRB will have approved the study protocol. Consent forms will reference the relevant IRB.
A condition where a baby grows more slowly than expected during pregnancy, resulting in a smaller-than-average birth weight. Can be detected via prenatal ultrasound. Has various causes, including genetic factors.
L
A principle under IDEA that students with disabilities should be educated alongside their non-disabled peers to the maximum extent appropriate, with supplementary aids and services as needed. The IEP team determines the appropriate placement; there is a range from full inclusion in general education to specialized settings.
M
An imaging test that uses magnetic fields and radio waves to create detailed pictures of internal organs and structures, including the brain and spine. Does not use radiation. For brain structure evaluation, MRI provides more detail than a CT scan. Young children often require sedation to keep still.
N
An umbrella term for conditions that affect brain development, including intellectual disability, autism spectrum disorder, ADHD, communication disorders, and specific learning disabilities. SETD5 Syndrome is classified as a neurodevelopmental disorder.
The primary U.S. federal agency for medical and health research. NIH funds a large portion of rare disease research in the United States. The NIH Undiagnosed Diseases Program and the National Human Genome Research Institute are particularly relevant for rare genetic conditions.
A U.S.-based nonprofit organization dedicated to rare disease advocacy, research, education, and patient services. Maintains a disease database including entries on many rare genetic conditions. Offers patient assistance and connects families with advocacy resources.
O
A condition characterized by intrusive, recurring thoughts (obsessions) and/or repetitive behaviors or rituals (compulsions) that interfere with daily life. Can co-occur with autism and other neurodevelopmental conditions. Treated with cognitive behavioral therapy (CBT) and/or medication.
A comprehensive, authoritative online database of human genes and genetic conditions maintained by Johns Hopkins University. Used by clinicians and researchers to look up gene-disease relationships. SETD5 Syndrome has its own OMIM entry. Accessible at omim.org -- though written for a clinical audience.
Therapy focused on developing the fine motor, sensory processing, self-care, and daily living skills needed to participate in “occupations” -- for children, this means school, play, and family life. Provided in school, clinic, or home settings. Often addresses handwriting, sensory sensitivities, feeding, dressing, and functional independence.
P
A structured communication method that teaches individuals to use picture cards to request items, describe their environment, and comment. Often used as a stepping stone toward more complex communication for individuals with limited verbal speech.
The lead researcher responsible for a study. When you contact a research team about a study, the PI is typically the faculty member or scientist whose lab is running it. Consent forms and IRB approvals list the PI by name.
Therapy focused on gross motor skills, strength, balance, coordination, and mobility. PT addresses how a person moves -- sitting, standing, walking, running, climbing. Provided in school, clinic, or home settings, and often part of early intervention.
R
A type of research study considered the gold standard for testing whether a treatment works. Participants are randomly assigned to receive either the treatment or a control (often a placebo). RCTs are rare for ultra-rare conditions like SETD5 Syndrome due to small patient populations.
S
A variation at a single position in the DNA sequence across individuals. Some SNPs are benign and common; others can affect gene function. Pronounced “snip.” Used in genetic research and in some screening tests, though SNP arrays are not the same as diagnostic WES or WGS.
A legal trust structure that holds assets for a person with a disability without disqualifying them from means-tested benefits like SSI and Medicaid. A “third-party SNT” holds funds from family members (such as an inheritance); a “first-party SNT” holds the person’s own assets. An attorney specializing in special needs planning can help establish one.
A clinician who evaluates and treats communication, speech, language, and feeding/swallowing disorders. In schools, SLPs provide speech-language therapy and may assess the need for AAC. Also referred to as “speech therapy (ST)” or “speech therapy services.”
A condition in which the brain has difficulty receiving and responding to sensory information, leading to over- or under-sensitivity to stimuli (sound, touch, movement, taste, light). Note that SPD is not a standalone diagnosis in the DSM-5 but is widely recognized and addressed in OT practice. Sensory features often occur alongside ASD, ADHD, and other NDDs.
The U.S. federal agency that administers SSI, SSDI, and other Social Security programs. SSA maintains disability determination records, processes benefit applications, and conducts continuing disability reviews (CDRs).
A Social Security benefit for adults with disabilities who have a sufficient work history (or whose parents do). Different from SSI: SSDI is based on prior earnings, not financial need. Some adults with SETD5 Syndrome may qualify as “disabled adult children” on a parent’s record when the parent retires, becomes disabled, or dies.
A needs-based federal benefit program administered by SSA that provides monthly payments to people with disabilities (including children) who meet financial and disability criteria. SSI eligibility often carries Medicaid eligibility in most states. Asset and income rules apply.
V
A genetic change that has been identified but whose clinical significance is not yet known -- it may be disease-causing, benign, or neither. Receiving a VUS result can be frustrating. Over time, as more data accumulates, many VUS findings are reclassified. Your genetic counselor can explain what a VUS result means for your family and when to follow up for reclassification updates.
W
A genetic test that sequences all protein-coding regions of the genome (the “exome”), which contains the approximately 1% of DNA that codes for proteins. WES can detect single-nucleotide variants and small insertions/deletions in known genes. Often ordered as a trio (patient plus both parents) to help interpret results.
A genetic test that sequences the entire genome, including both coding and non-coding regions. More comprehensive than WES, and increasingly used as a first-line diagnostic test. Can detect a broader range of variant types including structural variants, repeat expansions, and changes in non-coding regulatory regions. More data to interpret, which can mean more variants of uncertain significance.
See also: Medical Terms in Plain Language -- definitions of full terms (not just abbreviations) from reports, appointments, and research.