Gene: PCNT2
Protein: pericentrin
Clinical characteristics:
- Progressive intrauterine growth retardation
- Small for gestational age, typical birth weight is 3 pounds
- Relative microcephaly appears over time
- Disproportionately small forearms with progressive shortening of distal limbs
- Thin delicate bones with progressive metaphyseal widening, may be subtle in newborns
- Prominent nose and eyes
- Microdontia, hypodontia, or dysplastic teeth
- Fine sparse hair
- Pigmentary dysplasia of the skin
- Cerebral vascular abnormalities (moyamoya disease) in 20%, can predispose to stroke
Inheritance pattern: Autosomal recessive
What this test can tell us:
Testing is performed by sequencing all exons and surrounding intronic regions of the PCNT gene. This will detect point mutations, small deletions, and small insertions. It will not detect a partial or whole gene deletion or duplication.
PCNT2 is the only gene known to be associated with microcephalic osteodysplastic primordial dwarfism, type II (MOPD2). A negative test does not rule out a diagnosis of MOPD2 since the entire gene is not analyzed in this assay.
Sample requirements: Draw one or two 4-cc tubes of blood in EDTA/ purple top tube (minimum of 1-2 cc for infants)
Turn-around time: 4 weeks or less
CPT Codes and Cost:
89891 (x1) 83898 (x5) 83900 (x1) 83901 (x7) 83904 (x100) 83912 (x1) $2,200
Microcephalic Osteodysplastic Primordial Dwarfism Testing Packet
Additional Resources
- OMIM Entries
- MOPD II information from Nemours (written prior to PCNT2 gene discovery)