Methods and compositions for the identification and treatment of individuals having or likely to develop short stature
The instant disclosure relates to methods useful for the treatment or prevention of progressive growth failure in a subject in need thereof. The method may include the step of administering a PAPPA2 gene product to the subject. Also disclosed is the identification of a novel gene mutation that may be used as a marker to identify subjects particularly suited for such treatment. Compositions containing a therapeutically effective amount of PAPPA2 protein and a pharmaceutically acceptable carrier are also disclosed.
1. A method of treating progressive growth failure in a human subject diagnosed with idiopathic short stature and having a mutation in PAPP-A2, comprising administering plasma containing a PAPP-A2 enzyme intravenously to said human subject;
wherein said PAPP-A2 mutation is a homozygous loss-of-function mutation selected from D643fs25*, Ala1033Val, or a combination thereof;
wherein said mutation causes elevated serum levels of total IGF-I in said subject;
wherein said PAPP-A2 enzyme administered to said subject does not contain said homozygous loss-of-function mutation selected from D643fs25*, Ala1033Val, or a combination thereof; and
wherein said administration increases free IGF1 (fIGF1) in said subject.
2. The method of claim 1 , wherein said human subject is identified as small for gestational age without catch up growth.
3. The method of claim 1 , wherein said subject is administered said plasma during puberty, prior to puberty, or both.
4. The method of claim 1 , where said human subject has a height of about two standard deviations below the mid-parental target height.
5. The method of claim 1 , comprising co-administering a growth hormone to said subject.
6. The method of claim 5 , wherein said growth hormone is co-administered at a time period selected from one or both of simultaneously and sequentially.