Table 1.
Reported cases with homozygous mutations of the IGF1 gene.
| Woods et al. (1996) | Bonapace et al. (2003) | Walenkamp et al. (2005), Walenkamp and Wit (2007) | Netchine et al. (2009) | |
|---|---|---|---|---|
| Sex | Male | Male | Male | Male |
| Consanguinity | Yes | Yes | Yes | Yes |
| Birth weight SDS/g | −3.9/1400 | −4.0/1480 | −2.5/1420 | −2.5/2350 |
| Birth length SDS/cm | −5.4/37.8 | −6.5/41 | −3/39 | −3.7/44 |
| Growth SDS | −6.9 at 16 years | −6.2 at 1.6 years | −9 at 5 years | −4.5 at 3 years |
| Sensorineural hearing loss | Profound | Severe | Profound | No |
| IGF-I levels | Undetectable | 1.0 ng/mL | +7.3 SDS | Variable |
| IGF-I affinity-for IGF1R | Zero | Not studied | Extremely low | Partially reduced |
| Molecular defect | Deletion of exons 4–5 | Polymorphism | Missense mutation V44M | Missense mutation R36Q |