Predictive accuracy of genetic variants for eye color in a Kazakh population using the IrisPlex system.

OBJECTIVE: This study assesses the accuracy of the IrisPlex system, a genetic eye color prediction tool for forensic analysis, in the Kazakh population. The study compares previously published genotypes of 515 Kazakh individuals from varied geographical and ethnohistorical contexts with phenotypic data on their eye color, introduced for the first time in this research. RESULTS: The IrisPlex panel's effectiveness in predicting eye color in the Kazakh population was validated. It exhibited slightly lower accuracy than in Western European populations but was higher than in Siberian populations. The sensitivity was notably high for brown-eyed individuals (0.99), but further research is needed for blue and intermediate eye colors. This study establishes IrisPlex as a useful predictive tool in the Kazakh population and provides a basis for future investigations into the genetic basis of phenotypic variations in this diverse population.

The Chromatin Organization Close to SNP rs12913832, Involved in Eye Color Variation, Is Evolutionary Conserved in Vertebrates.

The most significant genetic influence on eye color pigmentation is attributed to the intronic SNP rs12913832 in the HERC2 gene, which interacts with the promoter region of the contiguous OCA2 gene. This interaction, through the formation of a chromatin loop, modulates the transcriptional activity of OCA2, directly affecting eye color pigmentation. Recent advancements in technology have elucidated the precise spatial organization of the genome within the cell nucleus, with chromatin architecture playing a pivotal role in regulating various genome functions. In this study, we investigated the organization of the chromatin close to the HERC2/OCA2 locus in human lymphocyte nuclei using fluorescence in situ hybridization (FISH) and high-throughput chromosome conformation capture (Hi-C) data. The 3 Mb of genomic DNA that belonged to the chromosomal region 15q12-q13.1 revealed the presence of three contiguous chromatin loops, which exhibited a different level of compaction depending on the presence of the A or G allele in the SNP rs12913832. Moreover, the analysis of the genomic organization of the genes has demonstrated that this chromosomal region is evolutionarily highly conserved, as evidenced by the analysis of syntenic regions in species from other Vertebrate classes. Thus, the role of rs12913832 variant is relevant not only in determining the transcriptional activation of the OCA2 gene but also in the chromatin compaction of a larger region, underscoring the critical role of chromatin organization in the proper regulation of the involved genes. It is crucial to consider the broader implications of this finding, especially regarding the potential regulatory role of similar polymorphisms located within intronic regions, which do not influence the same gene by modulating the splicing process, but they regulate the expression of adjacent genes. Therefore, caution should be exercised when utilizing whole-exome sequencing for diagnostic purposes, as intron sequences may provide valuable gene regulation information on the region where they reside. Thus, future research efforts should also be directed towards gaining a deeper understanding of the precise mechanisms underlying the role and mode of action of intronic SNPs in chromatin loop organization and transcriptional regulation.

The Level of Agreement between Self-Assessments and Examiner Assessments of Melanocytic Nevus Counts: Findings from an Evaluation of 4548 Double Assessments.

Cutaneous melanoma (CM) is a candidate for screening programs because its prognosis is excellent when diagnosed at an early disease stage. Targeted screening of those at high risk for developing CM, a cost-effective alternative to population-wide screening, requires valid procedures to identify the high-risk group. Self-assessment of the number of nevi has been suggested as a component of such procedures, but its validity has not yet been established. We analyzed the level of agreement between self-assessments and examiner assessments of the number of melanocytic nevi in the area between the wrist and the shoulder of both arms based on 4548 study subjects in whom mutually blinded double counting of nevi was performed. Nevus counting followed the IARC protocol. Study subjects received written instructions, photographs, a mirror, and a "nevometer" to support self-assessment of nevi larger than 2 mm. Nevus counts were categorized based on the quintiles of the distribution into five levels, defining a nevus score. Cohen's weighted kappa coefficient (κ) was estimated to measure the level of agreement. In the total sample, the agreement between self-assessments and examiner assessments was moderate (weighted κ = 0.596). Self-assessed nevus counts were higher than those determined by trained examiners (mean difference: 3.33 nevi). The level of agreement was independent of sociodemographic and cutaneous factors; however, participants' eye color had a significant impact on the level of agreement. Our findings show that even with comprehensive guidance, only a moderate level of agreement between self-assessed and examiner-assessed nevus counts can be achieved. Self-assessed nevus information does not appear to be reliable enough to be used in individual risk assessment to target screening activities.

Genotype data for 60 SNP genetic markers associated with eye, hair, skin color, ABO blood group, sex, core Y-chromosome haplogroups in Kazakh population.

OBJECTIVES: The collection of genotype data was conducted as an essential part of a pivotal research project with the goal of examining the genetic variability of skin, hair, and iris color among the Kazakh population. The data has practical application in the field of forensic DNA phenotyping (FDA). Due to the limited size of forensic databases from Central Asia (Kazakhstan), it is practically impossible to obtain an individual identification result based on forensic profiling of short tandem repeats (STRs). However, the pervasive use of the FDA necessitates validation of the currently employed set of genetic markers in a variety of global populations. No such data existed for the Kazakhs. The Phenotype Expert kit (DNA Research Center, LLC, Russia) was used for the first time in this study to collect data. DATA DESCRIPTION: The present study provides genotype data for a total of 60 SNP genetic markers, which were analyzed in a sample of 515 ethnic Kazakhs. The dataset comprises a total of 41 single nucleotide polymorphisms (SNPs) obtained from the HIrisPlex-S panel. Additionally, there are 4 SNPs specifically related to the AB0 gene, 1 marker associated with the AMELX/Y genes, and 14 SNPs corresponding to the primary haplogroups of the Y chromosome. The aforementioned data could prove valuable to researchers with an interest in investigating genetic variability and making predictions about phenotype based on eye color, hair color, skin color, AB0 blood group, gender, and biogeographic origin within the male lineage.

Characterization and RNA interference-mediated silencing of tryptophan 2,3-dioxygenase gene in Carpophilus hemipterus (L.) (Coleoptera: Nitidulidae).

Dried fruit beetle, Carpophilus hemipterus (Linnaeus, 1758) (Coleoptera: Nitidulidae), is a serious pest of ripened fresh fruit in the orchard and dried fruit in postprocessing storage. Despite the economic impact and widespread distribution of C. hemipterus, there is a lack of functional genomics research seeking to elucidate features of molecular physiology for improved pest management. Here, we report the characterization of the gene named Vermilion in C. hemipterus (ChVer) that encodes for tryptophan 2,3-dioxygenase. The Vermilion is frequently used as a visual marker for genomics approaches as tryptophan 2,3-dioxygenase is involved in the biosynthesis of eye coloration pigments in insects. We identified 1628 bp long full-length transcript of ChVer from transcriptomic database of C. hemipterus. The expression analysis among adult body parts revealed peak ChVer expression in head compared to thorax and abdomen, which is consistent with its role. Among the C. hemipterus developmental stages, peak ChVer expression was observed in first instar larva, second instar larva, and adult male stages, whereas the lowest levels of expression were seen in third instar larva, prepupa, and pupa. The nanoinjection of ChVer double-stranded RNA in larval C. hemipterus resulted in a significant reduction in ChVer transcript levels as well as caused a loss of eye color, that is, the white-eyed phenotype in adults. Characterization of visually traceable marker gene and robust RNA interference response seen in this study will enable genomics research is this important pest.

Sequence-Specific Relay Recognition of Multiple Anions: An Interplay between Proton Donors and Acceptors.

Ratiometric detection of analyte is highly deserving since the technique is free from background correction. This work reports the design and synthesis of a pyridine-end oligo p-phenylenevinylene (OPV) derivative, 1 and its application in ratiometric dual-mode (both colorimetric and fluorogenic) recognition of dual anions, bisulfate (LOD=12.5 ppb) followed by fluoride (LOD=18.2 ppb) by sequence-specific relay (SPR) technique. The colorless probe turns brown with addition of bisulfate and again becomes colorless with the sequential addition of fluoride ion. In addition to such naked-eye color change, interestingly the ratiometric spectroscopic signals are reversible and evidently, the probe is reusable for several cycles. Besides, in presence of bisulfate, the protonated probe molecules, owing to their larger amphiphilic characteristics, formed self-assembled nanostructures. In addition to colorimetric and fluorescent changes, 1 H NMR titration and systematic DFT study evidently establish the underneath proton transfer mechanisms. Such reusable OPV-based chemosensor particularly with the capability of naked-eye recognition of dual anions using the SPR technique is seminal and possibly the first report in the literature.

Forensic DNA Phenotyping: Genes and Genetic Variants for Eye Color Prediction.

In recent decades, the use of genetic polymorphisms related to specific phenotypes, such as eye color, has greatly contributed to the development of the research field called forensic DNA phenotyping (FDP), enabling the investigators of crime cases to reduce the number of suspects, making their work faster and more precise. Eye color is a polygenic phenotype, and many genetic variants have been highlighted, with the major contributor being the HERC2-OCA2 locus, where many single nucleotide variations (SNPs) were identified. Interestingly, the HERC2-OCA2 locus, containing the intronic SNP rs12913832, the major eye color determinant, shows a high level of evolutionary conservation across many species of vertebrates. Currently, there are some genetic panels to predict eye color by genomic DNA analysis, even if the exact role of the SNP variants in the formation of eye color is still poorly understood, with a low level of predictivity in the so-called intermediate eye color. Many variants in OCA2, HERC2, and other genes lie in introns or correspond to synonymous variants, highlighting greater complexity in the mechanism of action of such genes than a simple missense variation. Here, we show the main genes involved in oculocutaneous pigmentation and their structural and functional features, as well as which genetic variants show the highest level of eye color predictivity in currently used FDP assays. Despite the great recent advances and impact of FDP in criminal cases, it is necessary to enhance scientific research to better understand the mechanism of action behind each genetic variant involved in eye color, with the goal of obtaining higher levels of prediction.

A Multisample Approach in Forensic Phenotyping of Chronological Old Skeletal Remains Using Massive Parallel Sequencing (MPS) Technology.

It is very important to generate phenotypic results that are reliable when processing chronological old skeletal remains for cases involving the identification of missing persons. To improve the success of pigmentation prediction in Second World War victims, three bones from each of the eight skeletons analyzed were included in the study, which makes it possible to generate a consensus profile. The PowerQuant System was used for quantification, the ESI 17 Fast System was used for STR typing, and a customized version of the HIrisPlex panel was used for PCR-MPS. The HID Ion Chef Instrument was used for library preparation and templating. Sequencing was performed with the Ion GeneStudio S5 System. Identical full profiles and identical hair and eye color predictions were achieved from three bones analyzed per skeleton. Blue eye color was predicted in five skeletons and brown in three skeletons. Blond hair color was predicted in one skeleton, blond to dark blond in three skeletons, brown to dark brown in two skeletons, and dark brown to black in two skeletons. The reproducibility and reliability of the results proved the multisample analysis method to be beneficial for phenotyping chronological old skeletons because differences in DNA yields in different bone types provide a greater possibility of obtaining a better-quality consensus profile.

Eye and hair color prediction of an early medieval adult and subadult skeleton using massive parallel sequencing technology.

Phenotypic trait prediction in ancient DNA analysis can provide information about the external appearance of individuals from past human populations. Some studies predicting eye and hair color in ancient adult skeletons have been published, but not for ancient subadult skeletons, which are more prone to decay. In this study, eye and hair color were predicted for an early medieval adult skeleton and a subadult skeleton that was anthropologically characterized as a middle-aged man and a subadult of unknown sex about 6 years old. When processing the petrous bones, precautions were taken to prevent contamination with modern DNA. The MillMix tissue homogenizer was used for grinding, 0.5 g of bone powder was decalcified, and DNA was purified in Biorobot EZ1. The PowerQuant System was used for quantification and a customized version of the HIrisPlex panel for massive parallel sequencing (MPS) analysis. Library preparation and templating were performed on the HID Ion Chef Instrument and sequencing on the Ion GeneStudio S5 System. Up to 21 ng DNA/g of powder was obtained from ancient petrous bones. Clean negative controls and no matches with elimination database profiles confirmed no contamination issue. Brown eyes and dark brown or black hair were predicted for the adult skeleton and blue eyes and brown or dark brown hair for the subadult skeleton. The MPS analysis results obtained proved that it is possible to predict hair and eye color not only for an adult from the Early Middle Ages, but also for a subadult skeleton dating to this period.

Consistency of Eye Coloration Across Different Relationship Partners.

Studies have indicated that people are attracted to partners who resemble themselves or their parents, in terms of physical traits including eye color. We might anticipate this inclination to be relatively stable, giving rise to a sequential selection of similar partners who then represent an individual's "type". We tested this idea by examining whether people's sequential partners resembled each other at the level of eye color. We gathered details of the eye colors of the partners of participants (N = 579) across their adult romantic history (N = 3250 relationships), in three samples, comprising two samples which made use of self-reports from predominantly UK-based participants, and one which made use of publicly available information about celebrity relationship histories. Recorded partner eye colors comprised black (N = 39 partners), dark brown (N = 884), light brown (N = 393), hazel (N = 224), blue (N = 936), blue green (N = 245), grey (N = 34), and green (N = 229). We calculated the proportion of identical eye colors within each participant's relationship history, and compared that to 100,000 random permutations of our dataset, using t-tests to investigate if the eye color of partners across an individual's relationship history was biased relative to chance (i.e., if there was greater consistency, represented by higher calculated proportions of identical eye colors, in the original dataset than in the permutations). To account for possible eye color reporting errors and ethnic group matching, we ran the analyses restricted to White participants and to high-confidence eye color data; we then ran the analyses again in relation to the complete dataset. We found some limited evidence for some consistency of eye color across people's relationship histories in some of the samples only when using the complete dataset. We discuss the issues of small effect sizes, partner-report bias, and ethnic group matching in investigating partner consistency across time.

[A Biochip for Genotyping Polymorphisms Associated with Eye, Hair, Skin Color, AB0 Blood Group, Sex, Y Chromosome Core Haplogroup, and Its Application to Study the Slavic Population].

This paper presents a method for genotyping a panel of 60 single nucleotide polymorphisms (SNPs) using single-stage PCR followed by hybridization on a hydrogel biochip. The pool of analyzed polymorphisms consists of 41 SNPs included in the HIrisPlex-S panel, 4 SNPs of the AB0 gene (261G>Del, 297A>G, 657C>T, 681G>A), markers of the AMELX and AMELY genes, and 14 SNP markers of the Y chromosome haplogroups: B (M60), C (M130), D (CTS3946), E (M5388), G (P257), H (M2920), I (U179), J (M304), L (M185), N (M231), O (M175), Q (M1105), R (P224) and T (M272). These genetic data allow one to predict the phenotype of the desired person according to the characteristics of eye, hair, skin color, AB0 blood group, sex, and genogeographic origin in the male line. The setting protocol is simplified as much as possible to facilitate the introduction of the method into practice. The distribution of allele frequencies of the studied polymorphisms, as well as AB0 blood groups among the Slavs (N = 482), originating mainly from central Russia, was established.

Marker-assisted mapping enables forward genetic analysis in Aedes aegypti, an arboviral vector with vast recombination deserts.

Aedes aegypti is a major vector of arboviruses that cause dengue, chikungunya, yellow fever, and Zika. Although recent success in reverse genetics has facilitated rapid progress in basic and applied research, integration of forward genetics with modern technologies remains challenging in this important species, as up to 47% of its chromosome is refractory to genetic mapping due to extremely low rate of recombination. Here, we report the development of a marker-assisted mapping strategy to readily screen for and genotype only the rare but informative recombinants, drastically increasing both the resolution and signal-to-noise ratio. Using marker-assisted mapping, we mapped a transgene that was inserted in a >100-Mb recombination desert and a sex-linked spontaneous red-eye (re) mutation just outside the region. We subsequently determined, by CRISPR/Cas9-mediated knockout, that cardinal is the causal gene of re, which is the first forward genetic identification of a causal gene in Ae. aegypti. The identification of the causal gene of the sex-linked re mutation provides the molecular foundation for using gene editing to develop versatile and stable genetic sexing methods. To facilitate genome-wide forward genetics in Ae. aegypti, we generated and compiled a number of lines with markers throughout the genome. Thus, by overcoming the challenges presented by the vast recombination deserts and the scarcity of markers, we have shown that effective forward genetic analysis is increasingly feasible in this important arboviral vector species.

The Role of Eye Color in the Emergence of Tinnitus in Silence

Abstract Introduction Previous research suggests that African Americans are less likely than Caucasians to perceive tinnitus in sustained silence. Objective To evaluate the association between non-cutaneous melanin as indicated by eye color and the emergence of temporary tinnitus during a brief period of silence. Methods A cross-section of adults grouped according to their eye color were exposed to silence. A total of 62 adults, aged 18 to 35 years (10 males, 52 females) were required to sit in silence for 10 minutes, after which they filled out a questionnaire to report their eye color and any perception of sounds in the ears or head. Results In total, 63% of the participants perceived tinnitus while sitting in silence, and, of these 95% perceived the tinnitus sounds within 5 minutes of sitting in silence. Though African Americans were less likely to perceive tinnitus in silence, this difference was not significant (p = 0.6). After a period of silence, 69% of the subjects with light-colored eyes and 58% of the dark-eyed subjects perceived tinnitus. This difference was not statistically significant (χ2(1) = 0.77; p = 0.38). Conclusion When exposed to reduced auditory stimulation, 3 out of 5 normal-hearing people are likely to experience tinnitus. However, there was no relationship between eye color and the perception of tinnitus in silence. Although melanin has been shown to play a role in the protection of the ear against noise trauma and the effects of age-related hearing loss, its role in the emergence of tinnitus needs further investigation.

The Eyes Have It-for Idiopathic Pulmonary Fibrosis: a Preliminary Observation.

INTRODUCTION: The disease origins of idiopathic pulmonary fibrosis (IPF), which occurs at higher rates in certain races/ethnicities, are not understood. The highest rates occur in white persons of European descent, particularly those with light skin, who are also susceptible to lysosomal organelle dysfunction of the skin leading to fibroproliferative disease . We had observed clinically that the vast majority of patients with IPF had light-colored eyes, suggesting a phenotypic characteristic. METHODS: We pursued this observation through a research database from the USA Veterans Administration, a population that has a high occurrence of IPF due to predominance of elderly male smokers. Using this medical records database, which included facial photos, we compared the frequency of light (blue, green, hazel) and dark (light brown, brown) eyes among white patients diagnosed with IPF compared with a control group of lung granuloma only (no other radiologic evidence of interstitial lung disease). RESULTS: Light eye color was significantly more prevalent in patients with IPF than in the control group with lung granuloma [114/147 (77.6%) versus 129/263 (49.0%], p < 0.001), indicating that light-colored eyes are a phenotype associated with IPF . CONCLUSION: We provide evidence that light eye color is predominant among white persons with IPF.

Applicability of the IrisPlex system for eye color prediction in an admixed population from Argentina.

Eye color prediction based on an individual's genetic information is of interest in the field of forensic genetics. In recent years, researchers have studied different genes and markers associated with this externally visible characteristic and have developed methods for its prediction. The IrisPlex represents a validated tool for homogeneous populations, though its applicability in populations of mixed ancestry is limited, mainly regarding the prediction of intermediate eye colors. With the aim of validating the applicability of this system in an admixed population from Argentina (n = 302), we analyzed the six single nucleotide variants used in that multiplex for eye color and four additional SNPs, and evaluated its prediction ability. We also performed a genotype-phenotype association analysis. This system proved to be useful when dealing with the extreme ends of the eye color spectrum (blue and brown) but presented difficulties in determining the intermediate phenotypes (green), which were found in a large proportion of our population. We concluded that these genetic tools should be used with caution in admixed populations and that more studies are required in order to improve the prediction of intermediate phenotypes.

The Role of Eye Color in the Emergence of Tinnitus in Silence.

Introduction Previous research suggests that African Americans are less likely than Caucasians to perceive tinnitus in sustained silence. Objective To evaluate the association between non-cutaneous melanin as indicated by eye color and the emergence of temporary tinnitus during a brief period of silence. Methods A cross-section of adults grouped according to their eye color were exposed to silence. A total of 62 adults, aged 18 to 35 years (10 males, 52 females) were required to sit in silence for 10 minutes, after which they filled out a questionnaire to report their eye color and any perception of sounds in the ears or head. Results In total, 63% of the participants perceived tinnitus while sitting in silence, and, of these 95% perceived the tinnitus sounds within 5 minutes of sitting in silence. Though African Americans were less likely to perceive tinnitus in silence, this difference was not significant ( p = 0.6). After a period of silence, 69% of the subjects with light-colored eyes and 58% of the dark-eyed subjects perceived tinnitus. This difference was not statistically significant (χ 2 (1) = 0.77; p = 0.38). Conclusion When exposed to reduced auditory stimulation, 3 out of 5 normal-hearing people are likely to experience tinnitus. However, there was no relationship between eye color and the perception of tinnitus in silence. Although melanin has been shown to play a role in the protection of the ear against noise trauma and the effects of age-related hearing loss, its role in the emergence of tinnitus needs further investigation.

Experimental evidence that uniformly white sclera enhances the visibility of eye-gaze direction in humans and chimpanzees.

Hallmark social activities of humans, such as cooperation and cultural learning, involve eye-gaze signaling through joint attentional interaction and ostensive communication. The gaze-signaling and related cooperative-eye hypotheses posit that humans evolved unique external eye morphologies, including uniformly white sclera (the whites of the eye), to enhance the visibility of eye-gaze for conspecifics. However, experimental evidence is still lacking. This study tested the ability of human and chimpanzee participants to discriminate the eye-gaze directions of human and chimpanzee images in computerized tasks. We varied the level of brightness and size in the stimulus images to examine the robustness of the eye-gaze directional signal against simulated shading and distancing. We found that both humans and chimpanzees discriminated eye-gaze directions of humans better than those of chimpanzees, particularly in visually challenging conditions. Also, participants of both species discriminated the eye-gaze directions of chimpanzees better when the contrast polarity of the chimpanzee eye was reversed compared to when it was normal; namely, when the chimpanzee eye has human-like white sclera and a darker iris. Uniform whiteness in the sclera thus facilitates the visibility of eye-gaze direction even across species. Our findings thus support but also critically update the central premises of the gaze-signaling hypothesis.

From an early age, we are able to detect the direction others are looking in (known as eye-gaze) and make eye contact with each other to communicate. The front of the human eye has a large white area known as the sclera that surrounds the darker colored iris and pupil in the center. Compared to us, chimpanzees and other nonhuman great apes have sclerae that are much darker in color or at least not as uniformly white as human eyes. Some researchers believe that the white sclera of the human eye may have evolved to make it easier for other individuals to detect the direction of our gaze. However, there is a lack of experimental evidence as to whether white sclerae actually helps humans to distinguish the direction of eye-gaze. Here, Kano, Kawaguchi and Yeow presented human and chimpanzee participants with images of other humans and chimpanzees on a computer screen and asked them to indicate the direction of eye-gaze in each image. The experiments found that both humans and chimpanzees were better able to discriminate the directions of eye-gaze from the images of humans than those of chimpanzees, particularly when the images were smaller or more shaded. Moreover, artificially altering the eyes in the chimpanzee images so that they were more human-like ­ that is, had a light-colored sclera and a darker iris ­ enabled both humans and chimpanzees to better discriminate the eye-gaze directions of the chimpanzees. Kano, Kawaguchi and Yeow's findings indicate that white sclerae do indeed help both humans and chimpanzees to discriminate the direction of eye-gaze, even though only humans have white sclerae. This is likely because humans use eye-gaze in key social activities (including learning languages, coordinating to complete complex tasks and transmitting cultural information), indicating that white sclerae may have evolved to enhance human-specific communication. To learn more about this type of communication, future research could focus on finding out when white sclerae first evolved.

Cosmetic Change of the Apparent Color of the Eye: A Review on Surgical Alternatives, Outcomes and Complications.

An increasing number of people are seeking elective cosmetic change of eye color. We review the surgical techniques, outcomes and complications arising from the various existing surgical alternatives, including cosmetic iris implants-which based on the available evidence should be considered malpractice-as well as laser iris depigmentation and cosmetic keratopigmentation. Laser iris depigmentation has been used clinically for aesthetic purposes without receiving official approval or licensing. The technique can be performed in an outpatient clinic thanks to the use of neodymium: yttrium-aluminum-garnet (Nd:YAG) lasers, but scientific literature data about this treatment is very limited. Cosmetic iris implants are neither CE-marked nor Food and Drug Administration (FDA)-approved, and lead to severe complications arising from their placement including uveitis, hyphema, glaucoma, cataract, corneal endothelial damage and severe vision loss. Management of complications resulting from iris implants might require several surgical procedures, and the follow-up is difficult among these poorly informed patients. Keratopigmentation is the most extensively studied technique and had long been investigated before being introduced into clinical practice: already introduced centuries ago, it was recently developed, reporting adequate levels of safety and efficacy. The medium- and long-term cosmetic outcomes of keratopigmentation and patient satisfaction have been the subject of recent reports. The available level of evidence suggests that cosmetic keratopigmentation is the best evidence-supported surgical choice for patients seeking a permanent cosmetic eye color change. Still, additional investigation is needed to optimize the outcomes, minimize postoperative complications and further develop this and other new surgical alternatives such as laser procedures.

Eye color and the risk of skin cancer.

Melanoma, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most common skin cancers. The incidence rates of all three types of skin cancers have increased in the past three decades. Light pigmentary traits have been recognized as one of the host risk factors for skin cancer, but findings on associations between eye colors and risk of skin cancers have been inconsistent.We performed a prospective analysis to examine the association between eye colors and risk of skin cancers using the Health Professionals Follow-up Study (HPFS). Cox proportional hazard models were applied to estimate relative risks (RRs) and their 95% confidence intervals (CIs). Effect modifications due to hair color and skin reaction to sun were also examined.The HPFS included 35,662 males. During a median follow-up of 19 years (1988-2012), 445 melanoma, 1123 SCC, and 7198 BCC cases were documented. Compared to those whose eye colors were dark or brown, participants with hazel/green/medium and blue/light colors had a 24% (RR = 1.24, 95% CI: 1.06-1.45) and a 19% (RR = 1.19, 95% CI: 1.01-1.41) higher risk of SCC, respectively. Similarly, a higher risk of BCC was observed in participants with hazel/green/medium eye colors (RR = 1.16, 95% CI: 1.09-1.23) and blue/light eye colors (RR = 1.17, 95% CI: 1.10-1.25). We did not find significant associations between eye color and risk of melanoma. Lighter eye color was associated with increased risks of SCC and BCC among those with dark hair colors (p for interaction ≤ 0.02).In conclusion, in this large prospective study of men, we found that light eye colors were associated with higher risks of SCC and BCC, but not melanoma. Further studies are needed to confirm this association in other populations.

Blue Eyes Help Men Reduce the Cost of Cuckoldry.

Men with light eyes lack the dominant gene allele that codes for dark-brown eyes. Pairing with a woman who lacks the same allele must increase paternity confidence in these men, because any children with dark eyes would be extremely unlikely to have been fathered by them. This notion implies that men with light (blue or green) eyes should (1) prefer light-eyed women, especially in a long-term context, and (2) feel more threatened by light-eyed than by dark-eyed rivals. Yet because choosiness is costly and paternity concerns are entirely driven by the prospect of paternal investment, any such inclinations would be adaptive only in men who expect to invest in their children. Here I test these ideas using the data of over 1000 men who rated the facial attractiveness of potential partners, and the threat of potential rivals, whose eye color had been manipulated. Light-eyed men liked light-eyed women better (particularly as long-term companions), and feared light-eyed rivals more, than did dark-eyed men. An exploratory analysis showed that these large, robust effects disappeared in men who had felt rejected by their fathers while growing up-suggesting that such men are not expecting to invest in their own children either.