Continuous Eyebrow or Unibrow Genetics Practice Answer Key
Int J Trichology. 2017 Jul-Sep; 9(3): 105–107.
Synophrys: Epidemiological Study
Pramod Kumar
Department of Dermatology, Saham Hospital, Muscat, Oman
Abstract
Introduction:
Fusion of eyebrows above the bridge of nose is known as synophrys and is a normal variation. This variation is also recognized as a clinical feature of several genetic disorders, Cornelia De Lange syndrome being the commonest. Several studies, on aesthetics of face and eyebrows have been conducted, also on the role of eyebrows in emotional expression and nonverbal communication. A recent study has pointed a gene associated with synophrys. Surprisingly, however synophrys and its prevalence in the normal population is not known thus we conducted a study of its prevalence in Oman.
Methods:
All cases attending dermatology clinic at Saham hospital and their accompanying persons were examined for synophrys. The anonymous data was tabulated in a register and then it was transferred to computer system. Data was tabulated according to age, gender, presence of synophrys and any associated condition or genetic disorders or any chronic lifestyle disorders. It was analysed using SPSS 22 software.
Results:
We observed 927 subjects during the period of study. They ranged from ages of 4 months to 69 years. The males (68) outnumbered females (42). We found 110 cases (11.87%) who presented with synophrys.
Discussion:
The tendency of eyebrows to meet in the center of the face is known as synophrys. There is wide variation in the color, distribution and density of the eyebrow hair. Inheritance of synophrys however appears to be polygenic. Several genetic syndromes are associated with synophrys like Cornelia De Lange syndrome, which is the commonest. In our study we could not identify any genetic association in any of our cases. We studied the prevalence of synophrys in Omani population (11.87%).
Keywords: Eyebrows, hair, hypertrichosis, prevalence, synophrys
INTRODUCTION
When have humans not been fixated on eyebrows? from the Egyptian pharaohs who blackened their arches with kohl to 17th century women who used mouse hide brow wigs, to fashion's current swings between bleached and bold brow extremes; cultures have long prized the eyebrow in its limitless forms. Ancient Greeks had their own strange eyebrow rituals. Women used powdered minerals or soot to paint their brows black and appeared to have preferred a unibrow. Romans also had elaborate beauty rituals and favored a unibrow.[1]
Eyebrows are not just beauty fixation; they play an essential role in communication and facial recognition too. In a study, participants were able to identify personalities only with eyebrows on face with eyes digitally edited out of images, 60% of the time.[2]
Taber's dictionary defines Synophrys as "the fusion of eyebrows above the bridge of nose."[3] It is the presence of abundant hair between the eyebrows so they seem to join to form one long eyebrow hence also known as unibrow or monobrow.[4] Besides it is a recognized feature of Cornelia De Lange syndrome and many other genetic disorders associated with it.[5]
Synophrys or unibrow is part of variation of normal human eyebrow too. Historically, in some cultures synophrys are regarded as an attractive quality in men and women alike while Western culture finds it unappealing and is viewed as lack of sophistication.[6]
Arabian culture associates the fusion of eyebrows as a sign of beauty. The immense popularity tempts several women who have normal eyebrow to draw a black line thus joining them to fake a unibrow.
Thus, synophrys is an important facial feature which requires to be studied further. Its prevalence is not known; hence, we have attempted to find out the prevalence of synophrys in Omani population.
MATERIALS AND METHODS
This study was undertaken from May 2014 to January 2015 after ethical clearance from ethics and review committee. All the patients attending dermatology clinic and people accompanying them for whatsoever reason were also observed for the presence of synophrys. The data were recorded on a format, detailing the demographic features. The identities of participants were masked using identity number issued by record section for the electronic health records (EHR system Al Shifa 2.5,© Ministry of Health, Sultanate of Oman) instead of names of the participants. The data were tabulated in form of age, sex, presence of synophrys, reason for attending the clinic, and any associated genetic or chronic lifestyle diseases and analyzed using SPSS software 22 (IBM Corporation, U.S.A.).
RESULTS
In the duration of 8 months, we observed 927 participants for the presence of synophrys; one hundred and ten cases (11.87%) were found with synophrys [Figure 1]. The participants were within 4 months to 69 years of age. The data are shown in Table 1. The pattern of fusion of eyebrows was partial in some while it was complete in others. In participants with partial fusion eyebrows grew medially just short of joining, with a bunch of hair present on the glabella [Figure 2]. Some (11.82%) first-degree relatives [Table 2] of the cases with synophrys also had synophrys and this was not statistically significant (P = 0.767).
Table 1
Age distribution of cases with synophrys
Table 2
Synophrys in first-degree relatives
DISCUSSION
Texts[7] describe synophrys, when eyebrows may be profuse with a tendency to meet in the center of the face. There is a wide variation in the color, distribution, and density of the eyebrow hair. The inheritance of the appearance of the eyebrows is polygenic. Some hereditary variations are of no known significance, but others are associated with developmental defects or are part of a recognized syndrome.
Several genetic syndromes are associated with synophrys, this can be imagined when a search on OMIM[8] index (Online Mendelian Inheritance in Man) with the term as "synophrys" returns 113 results. Apart from normal variation, syndromes[5] associated with synophrys are:
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Cornelia De Lange syndrome (OMIM # 122470 – congenital muscular hypertrophy – cerebral syndrome)
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Basal cell nevus syndrome (Gorlin syndrome)
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Deletion 3p syndrome
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Duplication 3q syndrome
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Frontometaphyseal syndrome
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Hirschhorn-Cooper syndrome (chromosome partial deletion syndrome)
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Labard syndrome
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Partial trisomy chromosome 15
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Waardenburgh's syndrome (interoculoiridodermatoauditive dysplasia)
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Smith–Lemli–Opitz syndrome (cerebrohepatorenal syndrome)
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Thirteen trisomy syndrome (Patau syndrome)
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Mucopolysaccharidoses type III[9]
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May also present in cretinism.[10]
Kwashiorkor is also mentioned as an association in textbooks of dermatology[7,11] though it has not been substantiated with a valid reference.
In this study, however, we did not encounter any case of genetic disorder.
A recent study has found that eyebrow thickness is determined by a gene overlapping FOXL2 while synophrys has been shown to be associated with PAX3 gene in a genome-wide association scan study involving 6357 Latin Americans from five countries.[12]
Fusion of eyebrows may be complete as is viewed [Figure 1] or sometimes may be evolving or partial [Figure 2], when the two brows are spaced and there are hair on glabella. Hair may or may not grow later to complete such presentation. Thus, synophrys could be staged as Stage 1 when the brows are distant apart and there are distinct hair on glabella; stage 2 when the brows join to form unibrow without any empty space visible between them.
We have included the relatives of the cases in this study; therefore, there is obvious selection bias involved; a survey of general public different from those attending hospital would have been an ideal sample. This study included only Omani people hence it represents one ethnic group; however, recognizing the global prevalence of synophrys may be possible only after surveys in different population samples are available.
CONCLUSION
We have studied the prevalence (11.87%) of synophrys which has not been performed earlier. Many (11.82%) first-degree relatives also presented with synophrys. However, this association was not significant.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
Acknowledgment
The author is profusely thankful to thank Dr. Sujata Arya, M.D. for her unconditional support in statistical analysis of the data, review of the script.
REFERENCES
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Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5596643/
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