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. Although it is found more frequently in persons with several abnormal medical conditions, it is not predictive of any of these conditions since it is also found in persons with no abnormal medical conditions. It is found on at least one hand in 1.5% of the world's population.[1]
| Single transverse palmar crease | |
|---|---|
| Other names | Simian crease, simian line |
 | |
| Single transverse palmar crease on an infant's hand | |
| Specialty | Medical genetics |
Former name
editBecause it resembles the usual condition of non-human simians, it was, in the past, called the simian crease or simian line. These terms have widely fallen out of favor due to their pejorative connotation.[2]
Medical significance
editThe presence of a single transverse palmar crease has no medical significance. It is found in 1.5% of all people, and though it is found at a higher frequency in people with abnormal medical conditions, in every one of these conditions, many people do not have a single transverse palmar crease. Thus, it has a low predictive value.
Males are twice as likely as females to have this characteristic, which 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.[citation needed]
While it is often found in people with Down Syndrome,[3] many who have this syndrome do not have this crease, and thus is not a diagnostic indicator of Down Syndrome.
The presence of a single transverse palmar has been associated with several abnormal medical conditions—that is, it is found at a higher than 1.5% frequency, but in all of these conditions, many do not have this crease. Examples of conditions with such an association are fetal alcohol syndrome and the genetic chromosomal abnormalities, such as Down syndrome (chromosome 21), cri du chat syndrome (chromosome 5), Klinefelter syndrome, Wolf–Hirschhorn syndrome, Noonan syndrome (chromosome 12), Patau syndrome (chromosome 13), IDIC 15/Dup15q (chromosome 15), Edward's syndrome (chromosome 18), and Aarskog–Scott syndrome (X-linked recessive), or autosomal recessive disorder, such as leukocyte adhesion deficiency-2 (LAD2).[4] A unilateral single palmar crease was also reported in a case of chromosome 9 mutation causing nevoid basal cell carcinoma syndrome and Robinow syndrome.[5] It is also sometimes found on the hands of the affected side of patients with Poland syndrome and craniosynostosis.
A 1971 study refutes the hypothesis that the phenomenon is caused by fetal hand movement: the appearance of the crease occurs around the second month of gestation before the digital movement phase in the womb begins.[6]
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Single transverse palmar crease in an adult -
More common palmar creases in adults -
Bilateral single transverse palmar crease. The single transverse palmar crease is present on both hands of the individual.
See also
editReferences
edit- ^ Dar M.D., Hannah (6 August 1976). "Palmar Crease Variants and Their Clinical Significance" (PDF). Medical Encyclopedia. United States National Library of Medicine. Retrieved 20 October 2016.
- ^ Cooley, W. Carl; Wilson, Golder (2000). Preventive management of children with congenital anomalies and syndromes. Cambridge, UK: Cambridge University Press. p. 147. ISBN 978-0-521-77673-8.
- ^ McPherson M.D., Katrina (3 May 2004). "Simian crease". Medical Encyclopedia. United States National Library of Medicine. Retrieved 28 September 2006.
- "Definition of Simian crease". MedicineNet. MedicineNet, Inc. 2005. Archived from the original on 6 August 2012. Retrieved 28 September 2006.
- Hammer, Stephen J. McPhee, Gary D. (2010). "Pathophysiology of Selected Genetic Diseases". Pathophysiology of disease : an introduction to clinical medicine (6th ed.). New York: McGraw-Hill Medical. pp. Chapter 2. ISBN 9780071621670.{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ Marquardt, Thorsten; Brune, Thomas; Lühn, Kerstin; Zimmer, Klaus-Peter; Körner, Christian; Fabritz, Larissa; Van Der Werft, Natascha; Vormoor, Josef; Freeze, Hudson H.; Louwen, Frank; Biermann, Bettina; Harms, Eric; von Figura, Kurt; Vestweber, Dietmar; Koch, Hans Georg (30 June 1999). "Leukocyte adhesion deficiency II syndrome, a generalized defect in fucose metabolism". The Journal of Pediatrics. 134 (6): 681–8. doi:10.1016/S0022-3476(99)70281-7. PMC 7095022. PMID 10356134.
- ^ Olivieri, C.; Maraschio, P.; Caselli, D.; Martini, C.; Beluffi, G.; Maserati, E.; Danesino, C. (February 2003). "Interstitial deletion of chromosome 9, int del(9)(9q22.31-q31.2), including the genes causing multiple basal cell nevus syndrome and Robinow/brachydactyly 1 syndrome". European Journal of Pediatrics. 162 (2): 100–3. doi:10.1007/s00431-002-1116-4. PMID 12548386. S2CID 10565922.
- ^ Bali, R. S.; Chaube, Ramesh (July 1971). "On the Formulation of Palmar Creases". Zeitschrift für Morphologie und Anthropologie. 63 (1): 121–130. doi:10.1127/zma/63/1971/121. JSTOR 25755944. PMID 5105808. S2CID 36961365.
External links
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