Confirm diagnosis of Kabuki syndrome.
- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Characteristics: Distinctive facial appearance, most prominent in early childhood: arched eyebrows with sparse lateral third, long palpebral fissures with eversion of the lower eyelid, long dense eyelashes, blue sclerae, flat nasal tip, thin upper lip and full lower lip, large dysplastic ears. Renal, cardiac, skeletal, ocular, brain and dermatoglyphic abnormalities. Persistent fetal fingertip pads. Variable degree of intellectual disability.
Inheritance: Autosomal dominant.
Cause: Pathogenic germline KMT2D gene mutations.
Clinical Sensitivity: About 70 percent.
Methodology: Bidirectional sequencing of the entire KMT2D coding region and intron-exon boundaries.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Large deletions/duplications, deep intronic mutations, and some gene regulatory region mutations in KMT2D will not be detected. KDM6A mutations or mutations in other yet undiscovered genes associated with Kabuki syndrome will not be detected. Germline or somatic mosaicism will not be detected. Diagnostic errors can occur due to rare sequence variations.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|2009307||Kabuki Syndrome (KMT2D) Sequencing Spcm|
|2009308||Kabuki Syndrome (KMT2D) Sequencing Int|
- Kabuki Syndrome (MLL2) Sequencing