Is there a relationship between stature and age of onset of type 2 Diabetes?

AIMS: MSP1A and MSP1B polymorphic sites located in the GH genomic area have been found associated with GH response to insulin stimulation, with familiar short stature and with age at onset of Type 2 Diabetes (T2D). These observations prompted us to search for a possible relationship between stature and age at onset of the disease. METHODS: We have reexamined the data of 272 subjects with T2D mellitus. RESULTS: There is a highly significant negative correlation between stature and age at onset in non obese females (p < 0.001) but not in obese females and in males. In non obese females with stature within the first quartile the mean age at onset is 62 years while in those with a stature greater than the first quartlile the mean age at onset is 52 yesrs (p < 0.001). No difference is observed in obese females and males. CONCLUSIONS: These observations suggest the existence of different mechanisms underlying susceptibility to T2D. In addition to the well known increased risk due to obesity, endocrine dysfunctions related to genetic variability within the GH genomic area could represent another mechanism operating in non obese females. A cluster of non obese women characterized by short stature and late onset of diabetes seems to be separated by this mechanism from other women.

Smoking and the correlation between birth weight and placental weight. Evidence of interaction with maternal haptoglobin phenotype.

OBJECTIVE: The negative effects of cigarette smoking on human reproduction are well known. In a previous paper we have reported that negative effects of smoking on fertility are observed in women carrying the Haptoglobin (Hp) 2 phenotype only. In the present note we have examined the effect of smoking on the correlation between birth weight (BW) and placental weight (PW) and the interaction with maternal Hp phenotype. STUDY DESIGN: We have studied 584 consecutive newborns and their healthy mothers from the White population of the central area of Italy. Written informed consent was obtained by mothers to participate to this investigation that was approved by the Department of Pediatrics. Maternal Hp phenotype was determined by the method of Smithies as previously described. Differences between correlation coefficients were evaluated according to Snedecor and Cochran and according to Soper. Difference between means was calculated by Student's-t test using commercial software (SPSS). RESULTS: A strong decrease of correlation is seen in smoking mothers with Hp 2 phenotype only (p<0.0001). No statistically significant effect of smoking is present in mothers with Hp1 or Hp2-1 phenotype. A statistically significant decrease of BW in smoking mothers is observed in both Hp 2 mothers and in mothers carrying the Hp*1 allele. On the contrary a decrease of PW is observed only in mothers carrying Hp*1 allele but not in Hp 2 mothers. This indicates a concordant effect of smoking on BW and PW in mothers carrying Hp*1 allele but a discordant effect of BW and PW in Hp 2 mothers. This could explain the lack of correlation between BW and PW in smoking mothers carrying the Hp 2 phenotype. CONCLUSION: The combined phenotype smoking-Hp 2 shows different effects on BW and PW. Hp 2 has no effect on the decrease of BW determined by smoking but shows important effect in neutralizing the decrease of PW due to smoking: Hp polymorphism may be a factor with protective effects prevalent on placental growth as compared to fetal growth.

The relationship between p53 codon 72 genetic polymorphism and sperm parameters. A study of men with varicocele.

Purpose: Regulation of the apoptotic process has an important role in spermatogenesis. p53 has a prominent function in apoptosis and recent data suggest a relationship between varicocele and p53 codon 72 polymorphism and male infertility. This prompted us to study the relationship between this polymorphism and spermatic parameters. Methods: We studied 134 subjects with varicocele admitted consecutively to the outpatients Department of Infertility at the University of Rome La Sapienza. We investigated in these subjects the effect of a strong apoptosis inducer, the p53 codon 72 *Arg/*Arg genotype, on spermatic parameters.The p53 codon 72 genotype was determined by DNA analysis. Results: The proportion of spermatozoa with abnormal (curvilinear) motility is higher in men with the *Arg/*Arg genotype than in men carrying the *Pro allele (p = 0.003). No statistical significant relationship has been observed with spermatozoa concentration and atypical spermatozoa. Conclusions: We conclude: the p53 codon 72*Arg/*Arg genotype, with its strong apoptotic effects, negatively influences spermatozoa motility and male fertility.

Type 1 diabetes mellitus. Comparison between the association with PTPN22 genotype and the association with ACP1-ADA1 joint genotype.

AIMS: T1D has been found associated with PTPN22 and with ACP1-ADA1 joint genotype. In the present note we have collected further data to evaluate the relative importance of the two systems and to search for possible interaction of PTPN22 with ACP1-ADA1 joint genotype. METHODS: We have studied 314 children with T1D and 770 controls from the White population of Central Italy. ACP1, ADA1 and PTPN22 genotypes were determined by DNA analysis. Chi square test of independence was performed by SPSS program and three way contingency analysis by a log-linear model. RESULTS: Both carriers of *T allele of PTPN22 and subjects with ACP1 *A/*A and *A/*B genotypes carrying ADA1 *2 allele show an increase of susceptibility to T1D. There is evidence of additive effect (p=0.0002) but not of epistatic interaction. The association of T1D with ACP1-ADA1 joint genotype is stronger (OR=2.494, 95% C.I. 1.509-4.122) as compared to that with PTPN22 (OR=1.825, 95% C.I. 1.951-2.859). CONCLUSIONS: It has been suggested that the *T variant of PTPN22 inhibits T cell receptor signaling leading to failure to delete autoreactive T cells during intrathymic selection resulting in increased susceptibility to autoimmune disorders. The joint genotype ACP1 *A/*A and *A/*B carrying the ADA1 *2 allele shows a decreased activity of ACP1 resulting in a lowering of Zap70 activity that may decrease T cell receptor signaling with an additive effects to the inhibition due to the *T variant of PTPN22.

ACP1 genetic polymorphism and spermatic parameters in men with varicocele.

Platelet-derived growth factor (PDGF) and its receptors (PDGFRs) play a key role in the regulation of the embryonic and postnatal development of male gonads. PDGF deficiency is associated with severe spermatogenic impairment. ACP1 is a phosphoprotein tyrosine phosphatase that is able to dephosphorylate PDGFR, decreasing its activity as growth factor. The enzyme is polymorphic and shows strong differences in enzymatic activity among genotypes. At the Outpatient Department for Infertility, University of Rome La Sapienza, we investigated the effect of high-activity ACP1 genotype on spermatic parameters in 105 subjects referred to for varicocele. ACP1 genotype was determined by DNA analysis. In ACP1 *B/*C genotype, which shows the highest enzymatic activity, spermatic concentration is significantly lower and atypical spermatozoa are significantly more frequent as compared to other ACP1 genotypes. It is concluded that subjects carrying *B/*C genotype who represent about 10% of the population have a severe impairment of spermatic parameters in the presence of varicocele.

The association of PTPN22 polymorphism with endometriosis: effect of genetic and clinical factors.

OBJECTIVE: To investigate the possible effect of clinical and genetic variables on the association between PTPN22 and endometriosis. METHODS: PTPN22, ACP1 and p53 codon 72 genetic polymorphisms and duration of previous pharmacological treatment were studied. The study sample consisted of 132 women hospitalized for endometriosis diagnosed by laparoscopic intervention and histologically confirmed: 359 healthy blood donors were studied as controls. PTPN22, ACP1 and p53 codon 72 genotypes were determined by DNA analysis. Discriminant statistical analysis, logistic regression analysis, chi square of independence, power test and linear correlation were performed using SPSS programs. RESULTS: A significant increase of PTPN22 *T allele in endometriosis is observed in women carrying ACP1*C allele, in women carrying p53 codon 72 *Pro allele and in women with prolonged pharmacological treatment. CONCLUSIONS: PTPN22 may not be a primary factor in the etiology of endometriosis but may cooperate with clinical and genetic factors influencing susceptibility and clinical course of disease. These new observations point to a multifactorial origin of endometriosis and help to explain the reported differences between human populations concerning the association between PTPN22 and endometriosis.

Ak(1) genetic polymorphism and season of conception.

OBJECTIVE: The season of conception affects human reproduction, intrauterine growth, neonatal parameters, sex ratio, cognitive development and, in adult life, performance in many fields. Associations between polymorphic enzymes and season of conception have been also reported. In this study we searched for a possible association between season of conception and adenylate kinase locus 1 (Ak(1)). STUDY DESIGN: Two samples of 381 and 248 consecutively newborn infants from two Italian cities with different geographical positions and climatic conditions were considered. Three way contingency table analysis and Student t-test analysis were performed. RESULTS: Ak(1)2-1 phenotype is more frequent in males conceived in the summer-autumn period than in those conceived in winter-spring and this association depends on maternal Ak(1) phenotype (p=0.001). There is also an interaction between season of conception and Ak(1) phenotype concerning their effects on sex ratio and birth weight. CONCLUSION: The present data suggest a complex interaction involving seasonal cycles, maternal and foetal Ak(1) genotype and sex of foetus concerning their effects on intrauterine selection and neonatal parameters.

Atherosclerosis and PTPN22: a study in coronary artery disease.

OBJECTIVES: Recently, it has been shown that PTPN22 genetic polymorphism is associated with phenotypes related to the risk of atherosclerosis. In the present note, we have searched for a possible association of PTPN22 polymorphism with coronary artery disease (CAD). METHODS: One hundred and thirty-four non-diabetic subjects admitted to hospital for CAD and 174 healthy subjects (blood donors) were studied. PTPN22 genotypes were determined by DNA analysis. Statistical analyses were performed by SPSS programs. RESULTS: In CAD patients, the proportion of carriers of the *T allele of PTPN22 is significantly higher compared to healthy controls (OR 2.66; 95% CI 1.07-6.72). CONCLUSIONS: The present observation confirms the association of PTPN22 phenotype with atherosclerosis and suggests a role of immune mechanism in the pathogenesis of CAD.

Effect of smoking and ABO blood groups on maternal age at child bearing and on birth weight.

OBJECTIVE: The negative effects of cigarette smoking on human reproduction and on birth weight are well documented. On the other hand ABO system, encoding for glycosyltransferases, contributes to biosynthesis of antigens and oligosaccharide structures involved in blastocyst adhesion and intrauterine selection. In this paper we have searched for possible interaction between ABO system and smoking concerning their effects on maternal age at child bearing and on birth weight. STUDY DESIGN: We have studied 395 consecutive healthy puerperae from the White Caucasian population of Rome. ABO blood group was determined by standard laboratory methods. Three-way contingency table analysis was performed according to Sokal and Rohlf and Chi square test of independence by SPSS programs. RESULTS: The proportion of smokers is higher in A phenotype than in other ABO types among young puerperae (≤ 24 years) while it is lower in A phenotype than in other types among older women. The negative effects of smoke on birth weight is much more evident in women with A blood group than in women carrying other ABO phenotypes. The interaction between smoking and ABO blood groups concerning their effects on birth weight is influenced by gender of newborn and by maternal age. CONCLUSION: ABO blood groups and smoking could have a joint influence on maternal age at child bearing and on birth weight.

Is there a role of p53 codon 72 polymorphism in the susceptibility to type 2 diabetes in overweight subjects? A study in patients with cardiovascular diseases.

Two hundred and eighty six subjects with cardiovascular diseases and 147 healthy newborns were studied. P53 codon 72 polymorphism was determined by DNA analysis. The association between BMI and diabetes depends on p53 polymorphism: Odds Ratio shows a high significant association between BMI and diabetes in *Arg/*Arg subjects (p=0.00001). No significant association is observed in *Pro allele carriers (p=0.203).

ABH secretor genetic polymorphism: evidence of intrauterine selection.

OBJECTIVE: Fucosyltransferase locus 2 (FUT2) controls the presence or absence of blood group substances (A, B, H) in the saliva and other body secretions. Secretor/non-secretor phenotypes are associated with some metabolic and infectious diseases. ABO and FUT2 contribute to build up oligosaccharide structures of the cell surface that are important for blastocyst adhesion and resistance to microbial invasion. We investigated a possible selection on ABH secretor phenotypes during intrauterine life. STUDY DESIGN: Three hundred and fifty-six consecutive healthy puerperae and their newborn infants from the caucasian population of Rome were studied. Informed consent for study participation was obtained from the mothers to participate and the study was approved by the Institutional Review Board. ABH secretor Se phenotype was determined on saliva by standard laboratory procedure. RESULTS: Symmetry analysis of mother infant Se phenotype revealed a deficit of mother Se+/newborn Se- with respect to expected values. The asymmetry is present only in infants carrying the A blood group antigen. The asymmetry was dependent on several maternal and neonatal parameters including maternal age, smoke, parity and gestational duration. CONCLUSIONS: The data suggest intrauterine selection against Se- of the embryo carried by a Se+ mother. Such selection is dependent on factors influencing the maternal environment. The study could have practical importance in assessing the risk of infertility and success of artificial insemination.

Coronary artery disease: evidence of interaction between PTPN22 and p53 genetic polymorphisms.

OBJECTIVES: We recently reported an association between the PTPN22 genetic polymorphism and coronary artery disease (CAD) in nondiabetic subjects. Since recent studies suggest that p53 may be involved in coronary atherosclerosis, we have investigated a possible interaction between PTPN22 and p53 codon 72 genetic polymorphisms regarding their effects on susceptibility to CAD in nondiabetic subjects. METHODS: The genotypes of p53 codon 72 and PTPN22 were determined by DNA analysis in 128 nondiabetic subjects with CAD, 122 healthy blood donors and 117 nondiabetic subjects with cardiovascular diseases without CAD. RESULTS: In subjects with the *Arg/*Arg genotype of p53 codon 72, no association was observed between CAD and PTPN22. However, this association was very strong in subjects carrying the *Pro allele of p53 codon 72. Subjects carrying both the *T allele of PTPN22 and the *Pro allele of p53 were overrepresented in CAD nondiabetic cases relative to the other two groups (p = 0.001). CONCLUSIONS: Since both p53 and PTPN22 are involved in autoimmune inflammation, an interaction between the two systems appears biologically plausible. In the analysis of multifactorial disorders, the simultaneous analysis of multiple genes functionally related to diseases will provide a more productive approach than studies of single genetic factors performed from a Mendelian perspective.

A study of Adenosine-Deaminase genetic polymorphism in rheumatoid arthritis.

Recent investigations suggest that Adenosine Deaminase (ADA) could play a role in susceptibility to rheumatoid arthritis (RA). The purpose of our study is to investigate the possible role of genetic variability of ADA in the susceptibility to RA. We studied three intragenic ADA polymorphisms, ADA1, ADA2 and ADA6, in a sample of 91 subjects with RA and in 246 healthy subjects from the same Caucasian population and compared genotype and pairwise haplotype distributions between cases and controls. No statistically significant differences between RA and controls are observed for ADA genotypes. A border line difference for ADA1-ADA2 haplotype distribution is observed due to a decreased proportion of ADA1 *2/ADA2 *2 haplotype in RA compared to controls. Our data indicate a border line effect of ADA gene polymorphism on susceptibility to RA that need to be confirmed in other clinical settings.

A study of three polymorphic sites of ADA gene in colon cancer.

Adenosine inhibits the immune response in tumors. Adenosine deaminase (ADA) controls adenosine level and as ecto-enzyme acts as costimulatory molecule of adenosine receptors and/or CD26. We examined ADA1, ADA2, ADA6 polymorphic sites of ADA gene in 109 subjects with colon cancer from Rome's population and in 246 blood donors as controls from the same population. In colon cancer ADA1*2/ADA2*1 haplotype is more represented, while ADA1*2/ADA2*2 is less represented than in controls. ADA2*2/ADA6*2 is less represented in patients than in controls. Polymorphic sites of ADA might influence cell-mediated anti-tumor immune responses controlling adenosine level and extraenzymatic protein functions.

A study of three polymorphic sites of the ADA gene in children with type 1 diabetes mellitus.

BACKGROUND: Adenosine deaminase is a polymorphic enzyme that has an important role in immune functions and in the regulation of intracellular and extracellular concentrations of adenosine and adenosine receptor activity. AIM: To search for possible association of type 1 diabetes mellitus (DM1) with three loci haplotypes (ADA1, ADA2, ADA6) of the adenosine deaminase gene. PATIENTS: One hundred and eighty-nine consecutive children with DM1 from Sassari, Sardinia, and a control sample of 239 children from the same area were studied. METHODS: ADA loci genotypes were determined by DNA analysis. RESULTS: Compared to controls, diabetic boys show a decrease of the 2(2)/6(1) haplotype while diabetic girls show an increase of the same haplotype. This association was replicated in an independent sample from Continental Italy. CONCLUSIONS: The 2(2)/6(1) haplotype may exert a protective action in males but may increase susceptibility to DM1 in females: OR = 0.398, 95% CI 0.16-0.96 for males, and OR = 2.31, 95% CI 1.32-4.06 for females.

Is there a role of early neonatal events in susceptibility to allergy?

BACKGROUND: Several studies suggest a protective role of bilirubin against oxidative damage during the neonatal period. ADA1*2 allele has been found associated with higher bilirubin levels in newborns and with a protective action against bronchial asthma. Thus the relation between ADA1 and asthma could be mediated by events occurring during the early extrauterine life. Moreover the increased prevalence of allergic diseases in western populations parallels the widespread practice of phototherapy during the neonatal period. These observations prompted us to reevaluate our previous data and show new observations. METHODS: Data from 2729 previously studied subjects, from 53 subjects studied at birth and after 30 years and from a survey of phototherapy frequency in four Italian Hospital including 7392 newborns are reported. RESULTS: ADA1*2 allele carriers are less represented among asthmatic subjects than in controls (p=0.0004). ADA1*2 allele carriers among newborns undergoing phototherapy for hyperbilirubinemia is higher when compared to newborns not undergoing this treatment (p=0.006). In infants treated by phototherapy, the maximum bilirubin level attained during the first few days of life positively correlated with the ADA1*2 allele dose (p=0.001). Among subjects studied at birth, allergic rhinitis and/or conjunctivitis are more frequent among those treated with phototherapy than among those not treated (p=0.046). CONCLUSIONS: These observations support our hypothesis that ADA1*2 allele through an increase of bilirubin level in the neonatal period protects infants from oxidative stress and favours Th2→Th1 switching thus preventing allergic manifestations in later periods of life.

Body mass index and acid phosphatase locus 1 in diabetic disorders.

The polymorphic enzyme acid phosphatase locus 1 (ACP1) is a candidate gene for obesity disorders. The enzyme is able to dephosphorylate the insulin receptor. Our group has observed a lower plasma glucose level in diabetic subjects carrying the low activity ACP1 phenotypes A and BA, and a positive association between these genotypes and body mass index (BMI). We have now analysed the relationship between BMI and ACP1 in gestational diabetes and in women with type 1 diabetes. We have studied 106 Caucasian women with type 1 diabetes who had previously delivered a liveborn infant, 99 Caucasian women who had had gestational diabetes and 387 healthy fertile women from the same population as controls. ACP1 phenotype was determined by starch gel electrophoresis. In overweight women (BMI > 25), the proportion of low activity ACP1 phenotypes is much lower in type 1 diabetes than in gestational diabetes and in healthy females. In women with BMI ≤ 25, the proportion of low activity ACP1 phenotypes is slightly lower in gestational diabetes than in type 1 diabetes. Low activity ACP1 phenotypes have diverse effects on susceptibility to overweight depending on the class of diabetic disorder: in subjects with type 2 diabetes and in subjects with gestational diabetes low activity ACP1 phenotypes predispose to an increase in BMI, while in type 1 diabetes these ACP1 phenotypes seem to protect from overweight.