The Simian Line and Down Syndrome

Palm Readers and the Simian Line

Most human hands, in all races, have three main lines. Such lines appear on the soles of the feet also. The palm lines traditionally are called the Heart Line, Head Line, and Life Line. Medical people call these lines "flexion creases".

What is a simian line to a palm reader?

Sometimes, the Heart Line and Head Line fuse to form a single line. This line is called a simian line. The name "simian" was adopted many years ago and comes from the fact that some monkeys have only one crease in their palm. Medical people call it a single palmar crease or a "simian crease." Males are twice as likely as females to have this condition.

Many structures develop in the fetus in the first few months of gestation. Palmar creases develop early, by the 11th to 12th week of life. Abnormalities in palmar creases may indicate problems with early development and be associated with other developmental disorders like Down Syndrome.

Does a simian line indicate there is a medical problem, physical or mental abnormality?

Palm readers agree: NO!

There are a few sever physical and mental conditions where the majority of people with that condition have one or both hands with simian lines. Therefore, most of the literature and research is done with these people. From this comes the belief that a simian line indicates an abnormality physically or mentally. However, there are many people with a simian line on one or both hands that do not have any physical or mental abnormalities.

[NOTE: An informal and unscientific survey on this web site for people with one or more simian lines indicates that the majority of the surveyors do not have more than the normal physical problems. You can see the results for all questions in graphic form here.]

The Simian Line Appears Also in These Rare Medical Conditions

Aarskog syndrome is an inherited disease characterized by short stature, facial abnormalities, musculoskeletal, and genital anomalies. The people have one or more simian crease.

An even more rare condition is called "cri du chat syndrome" (Cry of the Cat syndrome) The syndrome's name is based on the infant's cry, which is high pitched and sounds like a cat. The cri du chat syndrome is caused by a missing part of chromosome 5. The cause of this rare chromosomal deletion is not known. Between 1 in 20,000 and 1 in 50,000 babies are affected. Infants with cri du chat syndrome commonly have a simian line. They also have an extensive grouping of abnormalities with severe mental retardation being the most important.