**Freckles**
How to define freckles:
Freckles are caused by genetic factors. The "freckle gene" increases the activity of tyrosinase in the basal layer under ultraviolet light exposure, leading to the formation of melanin, which results in freckles, also known as genetic spots. These spots originate during the fetal stage and are innate fixed features. Hereditary freckles are divided into dominant spots and recessive spots. Dominant spots typically begin to form between the ages of 6 and 12, reaching their peak around age 18. Recessive spots, on the other hand, often appear on the face after pregnancy-related hormonal changes occur. This is why some people classify freckles into congenital and acquired types. In reality, hormonal changes during pregnancy can stimulate the emergence of hidden freckles rather than indicating that freckles develop later in life. All freckles are caused by genetic factors. Freckles have a characteristic of skipping generations in heredity, which explains why some children may develop freckles even if neither parent has them. Although one or both parents may not exhibit visible freckles, they may carry the freckle gene and pass it on to their offspring.
**Freckles**
Medical term. Refers to scattered brownish-black spots appearing on areas such as the face. Mentioned in *The True Lineage of Surgery* (Volume 4). Commonly known as sparrow spots. The causes are often attributed to fire stagnation in the blood or wind-heat in the lung meridian. Treatments include applying Yung Rong Powder mixed with water to the affected area or using white茯苓(fu ling) powder for topical application.