Table 1 A clinical comparison between KAL1 and KAL2 genetic forms of Kallmann syndrome
From: Kallmann syndrome
Genetic form | KAL1 | KAL2 |
|---|---|---|
Gene (location) | KAL1 (Xp22.3) | FGFR1 (8p12) |
Mode of transmission | X chromosome-linked | Autosomal dominant (incomplete penetrance) |
Smell deficiency | Hyposmia to anosmia | None to anosmia |
Hypogonadism | Usually severe | Highly variable |
Non-reproductive and non-olfactory anomalies | ||
Bimanual synkinesis | Yes (>75%) | Uncommon |
Renal agenesis | Yes (30%) | Not reported |
Cleft lip/palate | No, but high arched palate | Yes (25–30%) |
Tooth agenesis | Yes | Yes (frequent?) |
Hearing impairment | Yes (unknown frequency) | Yes (unknown frequency) |
Other anomalies | Pes cavus, ptosis | Corpus callosum agenesis, external ear hypoplasia, absent nasal cartilage, hand/foot skeletal anomalies, iris coloboma |
