Single transverse palmar crease on an infant's hand

In humans, a single transverse palmar crease is a single crease that extends across the palm of the hand, formed by the fusion of the two palmar creases that people typically have.^[1][2] Because it resembles the usual condition of non-human simians, it is also known as a simian crease or simian line, although these terms have fallen out of favor due to its pejorative connotation.^[3]

[edit] Medical

The presence of a single transverse palmar crease can be, but is not always, a symptom associated with abnormal medical conditions, such as Fetal alcohol syndrome, or with genetic chromosomal abnormalities, including Down syndrome (chromosome 21), cri du chat syndrome (chromosome 5), Noonan syndrome (chromosome 12), Patau syndrome (chromosome 13), Edward's syndrome (chromosome 18), and Aarskog-Scott syndrome (X-linked recessive). Bilateral or unilateral single palmar creases are also associated with aberrations on chromosome 9^[4]. Also sometimes found on hand of affected side of patients with Poland Syndrome.

Males are twice as likely as females to have this characteristic, and it tends to run in families. In its non-symptomatic form, it is more common among Asians and native Americans than among other populations, and in some families there is a tendency to inherit the condition unilaterally, that is, on one hand only.

[edit] Additional images

Single tranverse palmar crease in an adult

Normal palmar creases in an adult

[edit] See also

• Dermatoglyphics
• Palm reading

[edit] References

1. ^ McPherson M.D., Katrina (2004-05-03). "Simian crease". Medical Encyclopedia. United States National Library of Medicine. http://www.nlm.nih.gov/medlineplus/ency/imagepages/17226.htm. Retrieved 2006-09-28. 
2. ^ "Definition of Simian crease". MedicineNet. MedicineNet, Inc.. 2005. http://www.medterms.com/script/main/art.asp?articlekey=40405. Retrieved 2006-09-28. 
3. ^ Cooley, W. Carl; Wilson, Golder (2000). Preventive management of children with congenital anomalies and syndromes. Cambridge, UK: Cambridge University Press. p. 147. ISBN 0-521-77673-2. 
4. ^ [1]

[edit] External links

• An example of a single transverse palmar crease
• Simian crease information, news & medical research