Relation between phenotype and banal melanocytic naevi.

Area of Science:

• Dermatology
• Epidemiology
• Genetics

Background:

• Melanocytic nevi (moles) are common skin lesions.
• Understanding risk factors for mole development is crucial for melanoma pathogenesis research.
• Phenotypic factors' association with mole count in white populations remains under-explored.

Purpose of the Study:

• To investigate the relationship between phenotypic characteristics and the number of melanocytic nevi in white adults.
• To identify potential risk factors for mole development relevant to malignant melanoma pathogenesis.

Main Methods:

• Cross-sectional study involving 197 white adult participants.
• Dermatological examination by four specialists to count melanocytic nevi.
• Correlation analysis between naevus counts and various phenotypic traits (skin type, eye color, hair color) and hormonal factors.

Main Results:

• Significant positive associations were found between a high number of melanocytic nevi and easy tanning ability (skin types 3 and 4; RR 4.6).
• Increased mole counts were also associated with brown/hazel eyes (RR 3.5), green/grey eyes (RR 3.5), and brown/black hair (RR 3.7).
• No significant associations were observed between naevus counts and parity or the use of oral contraceptives or other steroid hormones.

Conclusions:

• Phenotypic factors, specifically easy tanning, eye color, and hair color, are significantly associated with the number of melanocytic nevi in white adults.
• This study provides the first evidence of a link between melanocytic nevi and phenotypic factors in a white population.
• These findings may contribute to a better understanding of melanoma pathogenesis by identifying individuals with a higher propensity for mole development.