Analysis of the sequence of the variant exon-8 of fibroblastic Fas gene in keloid

Yongbo LIU; Xiaojun LIU; Jianhua GAO; Hongjie DUAN

ABSTRACT

BACKGROUND:

Keloid is the outcome of wound-healing process,and the result of massive accumulation of life-prolonged fibroblasts with gene mutation as well as the excessive synthesis of collagenous fibers.

OBJECTIVE:

To probe the relationship between the fibroblasts and the mutations of the exon-8 of Fas gene in keloid.

DESIGN:

An open study with gene sequence as the subjects of observation.

SETTING:

The Department of Plastic Surgery of Southern Hospital of the First Military Medical University.

PARTICIPANTS:

This experiment was carried out at the Tropical Disease Research Institute of the First Military Medical University of Chinese PLA in 2001. All keloid and hypertrophic scar tissues were obtained from the patients who received orthopedic surgical operations at the Southern Hospital, including 15 patients with keloid whose pathological areas were located respectively at the earlobe and the prothorax and 12patients with hypertrophic scars whose pathological areas being located at the instep and the elbow. At the same time, normal skin and the peripheral blood samples from the patients themselves with keloid were taken as the self-control and the skin and the peripheral blood samples from the normal people and the patients with hypertrophic scars were taken as the normal control.

METHODS:

PCR-SCCM technique and gene sequence analysis were used to detect the gene structure of exon-8 in the Fas gene from 15 patients.MAIN OUTCOME

MEASURES:

The gene structure of exon-8 in the Fas gene derived from the tissues and the peripheral blood samples of all the groups.

RESULTS:

① Heterozygous loss was observed in the exon-8 of the Fas gene in all 15 keloid patients; ② Gene sequence was found to be abnormal in 11 cases out of 15 keloid patients, presenting gene mutation in 4 loci.

CONCLUSION:

Heterozygous loss and gene mutation was detected in the exon 8 of Fas gene of keloid, suggesting that Fas protein in keloid has functional defect that is closely associated with gene mutation.