Situs inversus

Situs inversus (lat. inverted position ) is the medical term for the frame of a heterotaxy, a rare, but not in itself pathological peculiarity of anatomy, in which organs are mirrored on the other side of the body.

Situs inversus in humans

The Situs inversus occurs ( Kartagener's syndrome) in approximately one 8000-25000 people and in half of the people with primary ciliary dyskinesia. In people with this heterotaxy, the liver is, for example, on the left and in contrast, the spleen on the right side.

Medical concerns

To appendicitis ( appendicitis ) can not be overlooked, it must be borne in pain in the left lower abdomen and in the possibility of situs inversus.

According to the mirror-image position of the heart ( dextrocardia, large dexios = " right " cardiac = " cardiac " ) needs to be adjusted, the derivation of the ECG; it must be attached to a mirror image of the chest, inter alia, in the chest leads the electrodes. In some people with Patau syndrome ( trisomy 13), dextrocardia is present, while the other institutions are still created as usual.

Situs inversus in animals

Snails usually have right-handed snail shells. The incidence of left-handed snails is estimated at approximately 1:10,000 to 1:1,000,000. In such animals, referred to as a worm kings, and all organs ( eg heart, respiratory and genital opening ) are laterally reversed.

This is due to the hiking snail ( Lymnaea peregra ) a maternal factor, the dextral protein. This protein determines the direction of impact of the cilia in the morphogenesis - growth factors are distributed by the cilia and thus determine how the body expresses. Since it is a maternal factor, the dextral protein can be incorporated into the oocyte, thus ensuring even when homozygous recessive offspring for normal development.