Q98: Other sex chromosome abnormalities, male phenotype, not elsewhere classified

The group of conditions under the identifier Q98 in the ICD-10 WHO 2016 classification encompasses various sex chromosome abnormalities that are exhibited in individuals with male phenotype, who are not classified elsewhere. These abnormalities usually occur due to errors during the formation of sperm or egg cells, or due to issues that occur after conception. Affected individuals are genetically male and exhibit physical male characteristics, but they have unusual patterns of sex chromosomes that differ from the typical XY arrangement. Symptoms can range and may include delayed development, learning disabilities, infertility, and unique physical attributes such as short stature or unusual facial features. The progression of these conditions varies, largely depending on the specific chromosomal abnormality present. The diagnosis is commonly made through genetic testing. These conditions are not typically associated with a shortened lifespan, but aspects such as fertility or cognitive development can be affected.