2026 ICD-10-CM Diagnosis Code F78.A1SYNGAP1-related intellectual disability

ICD-10-CM Codes›F01–F99›F70-F79›F78

ICD-10-CM F78.A1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

F78.A1 is a billable ICD-10-CM diagnosis code for SYNGAP1-related intellectual disability. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Neurodevelopmental disorders.

Code Identity

ICD-10-CM Code
F78.A1
Billable Status
Yes — Valid for Submission
Code Describes
SYNGAP1-related intellectual disability
Short Description
SYNGAP1-related intellectual disability
Same as the full description in the CMS dataset.
Parent Code
F78.A
Other genetic related intellectual disabilities

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF70-F79Intellectual disabilities
CategoryF78Other intellectual disabilities
This CodeF78.A1SYNGAP1-related intellectual disability

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Code Also

  • , if applicable, any associated:
  • autism spectrum disorder F84.0
  • autistic disorder F84.0
  • encephalopathy G93.4
  • epilepsy and recurrent seizures G40
  • other pervasive developmental disorders F84.8
  • pervasive developmental disorder, NOS F84.9

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Disability, disabilities
      • intellectual
        • with
          • pathogenic SYNGAP1 (genetic) (variant)
    • Disability, disabilities
      • intellectual
        • genetic related
          • with
            • pathogenic SYNGAP1 (variant)
    • Disability, disabilities
      • intellectual
        • genetic related
          • SYNGAP1-related
    • Disability, disabilities
      • intellectual
        • SYNGAP1-related

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MBD014
Neurodevelopmental disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Developmental Disabilities

Developmental disabilities are conditions that are usually present at birth. They can affect a child's growth and development. These conditions can cause physical, learning, language, or behavior issues. They can include:

The full article covers:

  • What are developmental disabilities?
  • What causes developmental disabilities?
  • How are developmental disabilities diagnosed?
  • What are the treatments for developmental disabilities?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code History & ChangesHistory

Replacement F78.A1 replaces the following previously assigned code(s):

  • F78 - Other intellectual disabilities
FY 2022AddedAdded to the ICD-10-CM code setEffective October 1, 2021.
FY 2023–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About F78.A1Overview

Is F78.A1 (Other genetic related intellectual disabilities) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report SYNGAP1-related intellectual disability on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.