Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This case report concerns a 7-month-old infant with severe height retardation (-5.0 SD), typical growth hormone (GH)-deficient phenotype, and undetectable GH serum levels in response to three pharmacological stimuli. Diagnosis of isolated GH deficiency type 1A was confirmed by restriction endonuclease analysis of genomic DNA which pointed out GH-N gene deletion. The introduction of bio-methionyl-GH therapy in this patient was followed by a transient and clinically irrelevant appearance of low binding capacity GH antibodies as well as by a long-lasting catch-up growth (42.2 cm) which is continuing 44 months after beginning of treatment. This atypical pattern confirms that immune and growth response to exogenous GH in isolated GH deficiency 1A may be very heterogeneous.
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PMID:Long-lasting catch-up growth under bio-methionyl growth hormone treatment in an infant with isolated growth hormone deficiency type 1A. 129 98

Using restriction endonuclease analysis and a human growth hormone cDNA probe, we have found a Chinese family with a human growth hormone gene deletion. Two affected sibs are homozygous for a deletion of approximately 7.1 kb of DNA, which contains the normal human growth hormone gene. The patients' parents and grandmothers are heterozygous for the deleted gene. Their grandfathers are normal and homozygous for the hGH-N gene. All of them have normal stature.
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PMID:A Chinese familial growth hormone deficiency with a deletion of 7.1 kb of DNA. 232 87

We show the autoradiograms of DNA from one child affected of familial isolated growth hormone deficiency type I-A. Restriction endonuclease analysis of DNA isolated from leukocytes was done using 32P-labeled human GH cDNA clone as a probe. DNA analysis using the restriction endonuclease Bam HI revealed that the 3.8 kb restriction fragment, which contain the normal hGH-N gene, was absent. Since these deletions preclude production of any GH-N protein, affected individuals tend to be immunologically intolerant to exogenous GH. The child was homozygote and after treatment with exogenous GH developed a high titre of antibodies to GH and growth arrest. This is the first case of this genetic disorder studied in Spain.
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PMID:[Diagnosis by DNA analysis in familial isolated growth hormone deficiency type I-A]. 271 9

Using restriction endonuclease analysis of genomic DNA hybridized to a human chorionic somatomammotropin (hCS) complementary (c)DNA probe, we studied four young Jewish patients with isolated growth hormone deficiency (IGHD), and 15 family members. One family originated in Iraq, two in Yemen and one in Iran. Each patient was homozygous for a deletion of approximately 7.5 kilobases, which included the hGH-N gene. Three of the deletions were associated with the same restriction fragment length polymorphism haplotype, while the deletion in the child of Iranian descent was associated with a different haplotype. All the patients were treated with three injections per week of pituitary human growth hormone (hGH) for periods of 2 1/2 to 14 1/2 years. All had a good growth response. Three reached normal and one almost normal height. Repeated serum analyses revealed absence of anti-hGH antibodies. Thus, the presently described patients differ from those previously reported from Switzerland, Argentina and Japan, all of whom developed anti-hGH antibodies during treatment, with resultant slowing or arresting of growth. Expression of heterozygosity in family members was variable with regard to stature, hGH reserve and insulin-like growth factor I (IGF-I) levels. It is hypothesized that hGH-N gene deletion is not the sole determinant of immune response during hGH treatment, and that the difference between the current series and other cases needs further investigation.
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PMID:Human growth hormone gene deletion without antibody formation or growth arrest during treatment--a new disease entity? 300 92

An 11 year old Austrian boy with isolated growth hormone deficiency type I A is described. On institution of GH therapy at the age of 2 2/12 years there was only a short growth response and anti-GH-antibodies with high binding capacity were detected, and growth was inhibited. Examination of the nuclear DNA by restriction endonuclease analysis demonstrated a defect of the GH-N gene in the patient. The results suggest the deletion in this Austrian family is different from that seen in other patients. The parents were heterozygous for the deletion and had a subnormal GH response to stimulation with arginine, but their somatomedin-C concentrations and their heights were normal. The patients' sister was of normal height, hormone analyses were normal, and the GH-N gene was not affected.
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PMID:Growth hormone deficiency due to GH-N gene deletion in an Austrian family. 353 31

A Japanese family is described in which a 7-year-old child had isolated growth hormone deficiency type 1A, as described by Illig et al. He was shown to be homozygous for a deletion of the structural gene for hGH (hGH-N gene). Initially his growth rate responded well to hGH administration, but rapidly he developed high titers of hGH antibodies, and growth ceased. At that time, a somatomedin-C generation test gave negative results, suggesting that the growth arrest was related to the inability of hGH to generate somatomedin. Both parents were heterozygous for the hGH-N gene deletion and had a low hGH response to arginine and L-dopa tolerance tests, but had normal basal somatomedin-C levels and normal somatomedin-C generation tests. This family is the fourth to be reported with IGHD type 1A caused by deletion of the hGH-N gene. This cause of growth hormone deficiency can be distinguished from other severe autosomal recessive types of hGH deficiency by the demonstration of the deletion of hGH-N gene using restriction endonuclease analysis.
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PMID:Isolated growth hormone deficiency type 1A in a Japanese family. 653 75

It is well established that the human placenta produces a wide range of hormones similar to those secreted by the pituitary and hypothalamus. However, the physiological role and regulation of placental hormone synthesis and release are still largely unknown. GH (GH-N) is expressed in the pituitary, where it requires the tissue-specific transcription factor Pit-1. Chorionic somatomammotropin A (CS-A) and CS-B as well as the placental GH variant (GH-V), which also belong to the GH gene family and are located in the same chromosomal cluster, are expressed in the placental syncytiotrophoblast. The presence of Pit-1-binding sites in the CS-A and GH-V promoter regions predicts that Pit-1 may be expressed in the placenta. However, this has not yet been demonstrated. To examine possible similarities in the regulation of these genes in the pituitary and placenta, we studied the expression of pit-1 messenger ribonucleic acid (mRNA) in the human placenta, transformed human placental cells, and the JEG-3 choriocarcinoma cell line. Polymerase chain reaction (PCR) products of the expected size were amplified from first and third trimester placentas, transformed placental cells, and JEG-3 complementary DNA by reverse transcription-PCR. The pit-1-specific sequence was confirmed by restriction endonuclease digestion, Southern hybridization, and DNA sequencing. Human pituitary tissue was used as a positive control; no PCR product was obtained from hippocampus (negative control). In situ hybridization of placental tissue sections revealed the presence of pit-1 mRNA in first and third trimester syncytiotrophoblast. Pit-1 protein was localized by immunohistochemistry with the same tissue distribution and a nuclear localization pattern. These data demonstrate expression of pit-1 mRNA and Pit-1 protein in the human placenta, thus questioning its role as a pituitary-specific regulator of GH-N gene transcription. The expression of Pit-1 in the placenta, together with its previously demonstrated capability to bind to and activate the CS-A and the GH-V promoters, suggests that it may play a role in the regulation of hormones belonging to the GH gene family in both pituitary and placenta.
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PMID:Expression of pit-1 messenger ribonucleic acid and protein in the human placenta. 760 49

The human (h) protein hormones, growth hormone (hGH-N) and prolactin (hPRL), are mainly produced in the pituitary, whereas the human placenta expresses the other four members of the protein hormone gene family, designated placental lactogens (PL-A, PL-B, PL-L) and growth hormone variant (GH-V), GH-N stimulates somatic growth, supports nitrogen-, phosphate- and potassium retention and promotes lipolytic and anabolic metabolism, whereas PRL acts on the mammary gland and induces mammogenesis, lactogenesis and galactopoesis. Both hyperprolactinemia and growth hormone deficiency affect the onset of puberty and reproduction in man and mice. In addition to the glycoprotein hormones, these hormones play a role in the maintenance of testicular function. Our group previously demonstrated eutopic production of glycoprotein hormones hLH (human luteinizing hormone) and hCG (human chorionic gonadotropin) in the testis. We have now extended our investigations to the local testicular expression of protein hormones. By means of the molecular biology techniques of the reverse transcription-polymerase chain reaction (RT-PCR), Southern blot and by restriction endonuclease analyses of the generated PCR products we demonstrated the eutopic expression of genes coding for the protein hormones. GH-N gene transcripts were detected only in the pituitary and abundant PL-A/B and a few GH-V gene transcripts were demonstrable in the placenta. In contrast, in the testis GH/PL and PRL genes are transcribed. Since testicular protein hormone gene expression is rather low, these hormones may act locally and not as systemic factors; they presumably modulate the LH/CG-mediated testosterone biosynthesis and/or may act on the spermatogenesis.
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PMID:[The testis as eutopic production site of human growth hormone, placental lactogen and prolactin: possible autocrine/paracrine effects on testicular function]. 899 85