Facebook Pixel Code
Section banner image
Paediatric Laboratory Medicine

Skeletal Dysplasias: Hypochondroplasia

Clinical Significance

Achondroplasia (ACH) is characterized by abnormal bone growth that results in short stature with disproportionately short arms and legs, a large head, and characteristic facial features. Intelligence and life span are usually unaffected, although compression of the spinal cord and/or upper airway obstruction during infancy may result in medical complications.

Hypochondroplasia (HCH) is also characterized by short stature with disproportionately short arms and legs. The skeletal features are very similar to Achondroplasia but usually tend to be milder. Medical problems common to Achondroplasia occur less frequently in Hypochondroplasia, however deficits in mental capacity may be more common.

Test Name

Skeletal Dysplasias: Hypochondroplasia

Alternate Name/ Synonym

  • HCH
  • Hypochondrodysplasia

Gene Name

  • FGFR3

Test Code



Molecular Genetics


Targeted analysis of recurrent mutations

External Proficiency Testing


Turn Around Time

2 weeks (Prenatal samples), 2-3 weeks (Pregnancy/Urgent samples), 4-6 weeks (Routine)


Fibroblast growth factor receptor 3


Skeletal Dysplasias: Hypochondroplasia

Specimen Type

Blood; gDNA. 

For details about specimen requirements, please refer to: Specimen Type & Requirements (PDF).

Minimum Specimen Requirements

5-10 mL EDTA or ACD 0.5 mL EDTA (neonate); minimum 10 ug in 100 uL low TE (pH8.0)


Room Temperature

Special Requirements

Special Instructions for Genome Diagnostics Samples

If sample shipment >48 hours, ship on ice.

Approval is not required

CPT Codes


Shipping and Contact Information

The Hospital for Sick Children
Rapid Response Laboratory
170 Elizabeth Street, Room 3642
Toronto, ON
M5G 2G3
Phone: 416-813-7200
Phone: 1-855-381-3212


Interpretation is provided in report