SNPMiner Trials by Shray Alag


SNPMiner Trials: Clinical Trial Report


Report for Clinical Trial NCT03409510

Developed by Shray Alag, 2019.
SNP Clinical Trial Gene

Vitamin D and Skin Pigmentation in Healthy Humans Exposed to UVB

Skin pigmentation (melanin) absorbs ultra violet type B (UVB) radiation found in sunlight and is believed to be responsible for darker-skinned persons' generally low 25(OH)D status. This phenomenon is found in immigrants living in Northern countries and their 25(OH)D responses to UVB-irradiation seem low. We hypothesized that objectively measured skin pigmentation and/or pigment genes influence UVB-induced 25(OH)D increase significantly in combination with other influential parameters. The influence of objectively measured constitutive and facultative skin pigmentation on UVB-induced 25(OH)D increase over time was investigated together with other possible influential parameters. These other influential parameters include sex, age, weight, height, BMI, number of fatty fish meals per week, Fitzpatrick Skin Type and 25(OH)D start level. The genetic parameters include 33 Vitamin D receptor and pigment SNPs. This is a single-centre, open and non-blinded clinical trial. No randomisation was used, as the participants were allocated into two groups based on their Fitzpatrick Skin type and ethnic origin. The light-skinned group included participants with Fitzpatrick Skin type II-IV and were of Northern origin (Denmark, the Faroe Islands and the UK). The darker-skinned included Fitzpatrick Skin Types V-VI originating from countries located at latitudes below 50 degrees N. Thus, it could be ensured that the participants represented a wide range of skin pigmentation. The light-skinned (N = 22) and the darker-skinned subjects (N = 18) were exposed to identical UVB doses on identical body areas over nine weeks with weekly measurements of 25(OH)D. The UVB-induced 25(OH)D synthesis was investigated in summer-pigmented skin with melanin throughout the epidermis and during winter when ambient UVB exposure is negligible. Demographic data (gender, age, weight, height, Fitzpatrick Skin Type, measured constitutive and facultative skin pigmentation (PPF)) was collected/measured and registered in prior to study start. The number of daily consumed fatty fish meals was recorded in a questionnaire. Serum 25(OH)D was analysed weekly.

NCT03409510 Healthy Volunteers

1 Interventions

Name: UVB radiation

Description: UVB treatment regimen: Week 1-2: 0.85 kilo Joule/m2 twice per week Week 3-7: 0.85 kilo Joule/m2 three times per week Week 8-9: 1.4 kilo Joule/m2 three times per week

Type: Radiation

Long-term UVB radiation


Primary Outcomes

Description: Serum 25(OH)D is a marker of vitamin D increase induced by UVB

Measure: Change in serum 25(OH)D

Time: Measured at study start and weekly over nine weeks

Purpose: Basic Science

Single Group Assignment


There are 2 SNPs

SNPs


1 rs1544410

The influence of the vitamin D receptor gene was investigated by genotyping the two single nucleotide polymorphisms (SNP), rs1544410 (BsmI) and rs2228570 (FokI), located in the gene (ENSG00000111424, Chromosome 12q13) as previously described.


2 rs2228570

The influence of the vitamin D receptor gene was investigated by genotyping the two single nucleotide polymorphisms (SNP), rs1544410 (BsmI) and rs2228570 (FokI), located in the gene (ENSG00000111424, Chromosome 12q13) as previously described.



HPO Nodes