ICD-10 · PDGM grouping
Q90-Q99 — Chromosomal abnormalities, not elsewhere classified
Every ICD-10-CM code in this range and the PDGM clinical group CMS assigns to it, read from the CMS grouper crosswalk v07.2.26.
ICD-10-CM FY2027 · CMS grouper v07.2.26
Codes in range
74
No clinical group
3
A period cannot be grouped from these.
Barred as primary
0
CMS rejects these in the primary position.
Where these codes group
71 of the 74 codes in Q90-Q99 group to MMTA - Other. A further 3 are assigned no clinical group at all, which means a 30-day period cannot be grouped from them.
Code families in Q90-Q99
One page per three-character family: every code in it, whether it can lead a claim, its clinical group and comorbidity subgroup.
- Q90Down syndrome4 codes
- Q91Trisomy 18 and Trisomy 138 codes
- Q92Other trisomies and partial trisomies of the autosomes, not elsewhere classified9 codes
- Q93Monosomies and deletions from the autosomes, not elsewhere classified14 codes
- Q95Balanced rearrangements and structural markers, not elsewhere classified7 codes
- Q96Turner's syndrome7 codes
- Q97Other sex chromosome abnormalities, female phenotype, not elsewhere classified6 codes
- Q98Other sex chromosome abnormalities, male phenotype, not elsewhere classified9 codes
- Q99Other chromosome abnormalities, not elsewhere classified10 codes
Every code in Q90-Q99
Descriptions are CMS’s own, abbreviated as CMS abbreviates them.
| Code | Description | Clinical group | Primary position |
|---|---|---|---|
| Q900 | Trisomy 21, nonmosaicism (meiotic nondisjunction) | A | Can lead a claim |
| Q901 | Trisomy 21, mosaicism (mitotic nondisjunction) | A | Can lead a claim |
| Q902 | Trisomy 21, translocation | A | Can lead a claim |
| Q909 | Down syndrome, unspecified | A | Can lead a claim |
| Q910 | Trisomy 18, nonmosaicism (meiotic nondisjunction) | A | Can lead a claim |
| Q911 | Trisomy 18, mosaicism (mitotic nondisjunction) | A | Can lead a claim |
| Q912 | Trisomy 18, translocation | A | Can lead a claim |
| Q913 | Trisomy 18, unspecified | A | Can lead a claim |
| Q914 | Trisomy 13, nonmosaicism (meiotic nondisjunction) | A | Can lead a claim |
| Q915 | Trisomy 13, mosaicism (mitotic nondisjunction) | A | Can lead a claim |
| Q916 | Trisomy 13, translocation | A | Can lead a claim |
| Q917 | Trisomy 13, unspecified | A | Can lead a claim |
| Q920 | Whole chromosome trisomy, nonmosaic (meiotic nondisjunction) | A | Can lead a claim |
| Q921 | Whole chromosome trisomy, mosaicism (mitotic nondisjunction) | A | Can lead a claim |
| Q922 | Partial trisomy | A | Can lead a claim |
| Q925 | Duplications with other complex rearrangements | A | Can lead a claim |
| Q9261 | Marker chromosomes in normal individual | A | Can lead a claim |
| Q9262 | Marker chromosomes in abnormal individual | A | Can lead a claim |
| Q927 | Triploidy and polyploidy | A | Can lead a claim |
| Q928 | Other specified trisomies and partial trisomies of autosomes | A | Can lead a claim |
| Q929 | Trisomy and partial trisomy of autosomes, unspecified | None | Cannot lead a claim |
| Q930 | Whole chromosome monosomy,nonmosaic (meiotic nondisjunction) | A | Can lead a claim |
| Q931 | Whole chromosome monosomy, mosaic (mitotic nondisjunction) | A | Can lead a claim |
| Q932 | Chromosome replaced with ring, dicentric or isochromosome | A | Can lead a claim |
| Q933 | Deletion of short arm of chromosome 4 | A | Can lead a claim |
| Q934 | Deletion of short arm of chromosome 5 | A | Can lead a claim |
| Q9351 | Angelman syndrome | A | Can lead a claim |
| Q9352 | Phelan-McDermid syndrome | A | Can lead a claim |
| Q9359 | Other deletions of part of a chromosome | A | Can lead a claim |
| Q937 | Deletions with other complex rearrangements | A | Can lead a claim |
| Q9381 | Velo-cardio-facial syndrome | A | Can lead a claim |
| Q9382 | Williams syndrome | A | Can lead a claim |
| Q9388 | Other microdeletions | A | Can lead a claim |
| Q9389 | Other deletions from the autosomes | A | Can lead a claim |
| Q939 | Deletion from autosomes, unspecified | None | Cannot lead a claim |
| Q950 | Balanced translocation and insertion in normal individual | A | Can lead a claim |
| Q951 | Chromosome inversion in normal individual | A | Can lead a claim |
| Q952 | Balanced autosomal rearrangement in abnormal individual | A | Can lead a claim |
| Q953 | Balanced sex/autosomal rearrangement in abnormal individual | A | Can lead a claim |
| Q955 | Individual with autosomal fragile site | A | Can lead a claim |
| Q958 | Other balanced rearrangements and structural markers | A | Can lead a claim |
| Q959 | Balanced rearrangement and structural marker, unspecified | A | Can lead a claim |
| Q960 | Karyotype 45, X | A | Can lead a claim |
| Q961 | Karyotype 46, X iso (Xq) | A | Can lead a claim |
| Q962 | Karyotype 46, X w abnormal sex chromosome, except iso (Xq) | A | Can lead a claim |
| Q963 | Mosaicism, 45, X/46, XX or XY | A | Can lead a claim |
| Q964 | Mosaic, 45, X/other cell line(s) w abnormal sex chromosome | A | Can lead a claim |
| Q968 | Other variants of Turner's syndrome | A | Can lead a claim |
| Q969 | Turner's syndrome, unspecified | A | Can lead a claim |
| Q970 | Karyotype 47, XXX | A | Can lead a claim |
| Q971 | Female with more than three X chromosomes | A | Can lead a claim |
| Q972 | Mosaicism, lines with various numbers of X chromosomes | A | Can lead a claim |
| Q973 | Female with 46, XY karyotype | A | Can lead a claim |
| Q978 | Oth sex chromosome abnormalities, female phenotype | A | Can lead a claim |
| Q979 | Sex chromosome abnormality, female phenotype, unspecified | A | Can lead a claim |
| Q980 | Klinefelter syndrome karyotype 47, XXY | A | Can lead a claim |
| Q981 | Klinefelter syndrome, male with more than two X chromosomes | A | Can lead a claim |
| Q983 | Other male with 46, XX karyotype | A | Can lead a claim |
| Q984 | Klinefelter syndrome, unspecified | A | Can lead a claim |
| Q985 | Karyotype 47, XYY | A | Can lead a claim |
| Q986 | Male with structurally abnormal sex chromosome | A | Can lead a claim |
| Q987 | Male with sex chromosome mosaicism | A | Can lead a claim |
| Q988 | Other specified sex chromosome abnormalities, male phenotype | A | Can lead a claim |
| Q989 | Sex chromosome abnormality, male phenotype, unspecified | A | Can lead a claim |
| Q990 | Chimera 46, XX/46, XY | A | Can lead a claim |
| Q991 | 46, XX true hermaphrodite | A | Can lead a claim |
| Q992 | Fragile X chromosome | A | Can lead a claim |
| Q99811 | Usher syndrome, type 1 | A | Can lead a claim |
| Q99812 | Usher syndrome, type 2 | A | Can lead a claim |
| Q99813 | Usher syndrome, type 3 | A | Can lead a claim |
| Q99818 | Other Usher syndrome | A | Can lead a claim |
| Q99819 | Usher syndrome, unspecified | A | Can lead a claim |
| Q9989 | Other specified chromosome abnormalities | A | Can lead a claim |
| Q999 | Chromosomal abnormality, unspecified | None | Cannot lead a claim |
Source: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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