There is also overlap between genes associated with situs ambiguus and primary ciliary dyskinesia, likely due to the important role of cilia is establishing left-right asymmetry. The planar cell polarity has an important role in positioning these cilia, and thus genes within this pathway are increasingly associated with situs ambiguus.Disrupted mitochondria function has also been recently linked to heterotaxy. Pathophysiology
Molecular and cellular mechanism
Several genes have been identified in normal development of the right-left axis. These genes have been extensively researched. Gene mutations that lead to atrial isomerism is a growing area of research. Mutations in genes that encode proteins in the TGF-beta pathway, including NODAL, NKX2-5, and ZIC3, have been linked to tetralogy of Fallot and hypoplastic left heart syndrome. Mutations in the ZIC3 gene, which encodes a zinc finger family transcription factor, is linked to a 50% risk of atrial isomerism in families. It is also an X-linked disorder, so testing for ZIC3 mutations is highly encouraged in male births.The most prevalent and best characterized genetic associations of heterotaxy include:

Classical pathology
Cardiac looping malformations:
Fallots tetralogy
transposition of the great vessels
Ventricular and atrial septal defects. Deranged abdominal organ asymmetry:
The stomach and spleen are prone to isolated reversal
The stomach, liver, and a single adrenal gland are occasionally found in the midline. Organ malformations:
asplenia and polysplenia often lead to sepsis
More rarely, the head of the pancreas fails to form
Horseshoe kidneys develop, which can lead to cancer, kidney stones, and/or infection. Malrotation errors cause volvulus and/or faulty peritoneal attachments, which completely obstruct the bowel.
Carbamate poisoning is poisoning due to exposure to carbamates. Carbamates are typically used as pesticides; however, some also have medical uses. Symptoms may be similar to organophosphate poisoning. == References ==