Age modulates the effect of DGAT1 deficiency on sebaceous gland morphology. (a and b) In 6-week-old male mice, the sebaceous glands (SG) and hair follicles (HF) appeared to be normal, regardless of Dgat genotype. (c and d) In 3-month-old male mice, DGAT1 deficiency was associated with atrophic sebaceous glands; for most hair follicles, sebaceous glands were not identifiable. Bar, 30 μm.