Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-gamma gene in first-degree relatives of subjects with polycystic ovary syndrome.
OBJECTIVE
This study was designed to examine the relationship between the Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-gamma (PPAR-gamma) gene and insulin resistance (IR) in first-degree relatives of subjects with polycystic ovary syndrome (PCOS).


METHODS
One hundred and twenty family members of 55 patients with PCOS and 80 unrelated healthy control subjects without a family history of diabetes or PCOS were studied. IR was assessed by homeostatic model assessment (HOMA-IR) and area under the curve (AUC) for insulin during an oral glucose tolerance test in subjects with normal glucose tolerance and controls. Genetic analysis of the PPAR-gamma gene Pro12Ala polymorphism was performed by restriction fragment length polymorphism.


RESULTS
Fasting insulin, HOMA-IR and AUC insulin were significantly higher in first-degree relatives of PCOS subjects than in controls. A significantly different allele distribution of the Pro12Ala polymorphism of PPAR-gamma was observed between the two groups, with the frequency of the variant Ala isoform being significantly reduced in the first-degree relatives of PCOS subjects (10.8%, 13 subjects) compared with the control group (22.5%, 18 subjects). All Pro12Ala polymorphisms of the PPAR-gamma gene were heterozygous. Compared with first-degree relatives of PCOS subjects with the Pro12Pro polymorphism of PPAR-gamma, first-degree relatives of PCOS subjects with the Pro12Ala polymorphism had low fasting insulin, HOMA-IR and AUC insulin levels. The combined prevalence rate for impaired glucose tolerance, impaired fasting glucose and diabetes was 40% (16 subjects) in mothers and 52% (20 subjects) in fathers of PCOS women.


CONCLUSIONS
Our findings suggest that Pro12Ala PPAR-gamma gene polymorphism may be protective against IR and might prevent the development of diabetes mellitus in the first-degree relatives of subjects with PCOS.
Yilmaz
Murat
M
Department of Endocrinology and Metabolism, Faculty of Medicine, Kirikkale University, Turkey. murartt@hotmail.com
Ergün
Mehmet Ali
MA
Karakoç
Ayhan
A
Yurtçu
Erkan
E
Yetkin
Ilhan
I
Ayvaz
Göksun
G
Cakir
Nuri
N
Arslan
Metin
M
D000293:Adolescent; D000328:Adult; D000483:Alleles; D015992:Body Mass Index; D003920:Diabetes Mellitus / Q000235:genetics; D005215:Fasting; D005260:Female; D005787:Gene Frequency; D018149:Glucose Intolerance / Q000235:genetics; D005951:Glucose Tolerance Test; D006579:Heterozygote; D006706:Homeostasis; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000235:genetics; D008297:Male; D008875:Middle Aged; D047495:PPAR gamma / Q000235:genetics*; D011085:Polycystic Ovary Syndrome / Q000235:genetics*; D011110:Polymorphism, Genetic
D007328:Insulin; D047495:PPAR gamma