2026 ICD-10-CM Diagnosis Code Q98Other sex chromosome abnormalities, male phenotype, not elsewhere classified

ICD-10-CM Codes›Q00-Q99›Q90-Q99›Q98

ICD-10-CM Q98
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Q98 is a non-billable ICD-10-CM category code for other sex chromosome abnormalities, male phenotype, not elsewhere classified, so it cannot be submitted on claims. Use a more specific code from this category instead, such as Q98.0, Q98.1, Q98.3, and Q98.4.

Code Identity

ICD-10-CM Code
Q98
Billable Status
No — Non-Billable Category
Code Describes
Other sex chromosome abnormalities, male phenotype, not elsewhere classified
Chapter
Q90-Q99
Chromosomal abnormalities, not elsewhere classified

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ90-Q99Chromosomal abnormalities, not elsewhere classified
CategoryQ98Other sex chromosome abnormalities, male phenotype, not elsewhere classified
This CodeQ98Other sex chromosome abnormalities, male phenotype, not elsewhere classified

Specific Coding for Oth sex chromosome abnormalities, male phenotype, NECOverview

Non-specific codes like Q98 require more characters. Use one of these billable codes instead:

  • Use Q98.0 for Klinefelter syndrome karyotype 47, XXY

  • Use Q98.1 for Klinefelter syndrome, male with more than two X chromosomes

  • Use Q98.3 for Other male with 46, XX karyotype

  • Use Q98.4 for Klinefelter syndrome, unspecified

  • Use Q98.5 for Karyotype 47, XYY

  • Use Q98.6 for Male with structurally abnormal sex chromosome

  • Use Q98.7 for Male with sex chromosome mosaicism

  • Use Q98.8 for Other specified sex chromosome abnormalities, male phenotype

  • Use Q98.9 for Sex chromosome abnormality, male phenotype, unspecified

Patient EducationClinical

Genetic Disorders

Genetic disorders are health conditions caused by changes (also called mutations or variants) in your genes. Genes are parts of DNA found in your cells that carry instructions for how your body grows, develops, and functions. Many genes tell your body how to make proteins, which are needed for your body to work properly.

The full article covers:

  • What are genetic disorders?
  • What causes genetic disorders?
  • What are the types of genetic disorders?
  • What are the different ways a genetic disorder can be inherited?
  • How are genetic disorders diagnosed?

Read the full article at MedlinePlus

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

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Q98Overview

Is Q98 a billable code?

No. This is a category header that groups the codes for other sex chromosome abnormalities, male phenotype, not elsewhere classified, and headers cannot be submitted on claims. Claims for other sex chromosome abnormalities, male phenotype, not elsewhere classified need a more specific code from this category, such as Q98.0, Q98.1, and Q98.3.