A novel androgen receptor gene mutation in a Chinese patient with complete androgen insensitivity syndrome

Objective

To identify the underlying androgen receptor gene mutation in a Chinese patient with typical symptoms of complete androgen insensitivity syndrome.

Study design

A Chinese female phenotype with 46, XY karyotype was diagnosed because of primary amenorrhea. Mutations were determined by polymerase chain reaction followed by DNA sequencing.

Results

DNA sequencing of the androgen receptor gene showed a G2439T transition causing E442X mutation in exon 1 in the patient with complete androgen insensitivity syndrome. The E442X mutation was a new de novo non-sense mutation in exon 1 of the androgen receptor gene. This non-sense mutation is located in the N-terminal transactivation domain and leads to a predicted truncated protein of 441 amino acids with loss of the end part of the N-terminal transactivation domain, and the DNA-binding and ligand-binding domain.

Conclusion

This E442X non-sense point mutation has not been described previously in cases of androgen insensitivity syndrome, and could lead to the synthesis of a short truncated non-functional androgen receptor probably responsible for the phenotype of complete androgen insensitivity syndrome in the affected individual. Gonadectomy should be planned to eliminate the risk of gonadal malignancy.     

Androgen receptor gene mutation associated with complete androgen insensitivity syndrome and Sertoli cell adenoma.

We report a case of Sertoli cell adenoma in complete androgen insensitivity syndrome (CAIS) in a 22-year-old woman. Polymerase chain reaction-single strand conformation polymorphism and DNA sequencing revealed a single nucleotide substitution on exon 7 of the human androgen receptor (hAR) gene, resulting in a change of CGA (arginine) to CAA (glutamine) in codon 831.     

A double nucleotide insertion-induced frame-shift mutation of the androgen receptor gene in a familial complete androgen insensitivity syndrome

Objective

A wide spectrum of androgen receptor (AR) gene mutations has been reported in complete androgen insensitivity syndrome (CAIS). The molecular basis of androgen resistance was investigated in a female with familial CAIS.

Study design

AR gene and protein were investigated by PCR and direct sequencing and Western immunoblotting, respectively.

Results

Sequencing analysis of DNA of the patient identified a double nucleotide insertion in exon 4 that results in the frame-shift leading to premature terminal signal in the beginning of exon 6. This mutation predicted the synthesis of a truncated AR that lacks the entire ligand-binding molecules. Immunoblotting analysis of the gonad removed from the patient detected the mutated AR protein of 94 kDa. Positive control revealed the normal apparent molecular mass of 110 kDa. DNA sequencing of her mother demonstrated the presence of both canonical and mutated sequences in the exon 4 through 8.

Conclusion

These findings suggested that the previously undescribed insertion mutation in the AR gene is the cause of CAIS in this family.     

A unique point mutation in the androgen receptor gene in a family with complete androgen insensitivity syndrome.

OBJECTIVE: To further delineate the diversity of genetic alterations in the gene coding for the androgen receptor in individuals with the androgen insensitivity syndrome and to increase our understanding of the disease at the molecular level. DESIGN: This was a prospective study in which genomic deoxyribonucleic acid (DNA) from individuals with androgen insensitivity were examined through the polymerase chain reaction and DNA sequencing analysis. PATIENTS: Eleven complete and four individuals with partial androgen insensitivity syndrome were examined. RESULTS: Exons two through eight were grossly intact in all study subjects. Nucleotide sequence analysis revealed that three of three related family members with complete androgen insensitivity had the same guanine to adenine base substitution in exon five of the steroid-binding domain. CONCLUSION: The subsequent alanine to threonine amino acid conversion may have resulted in a configurational change of the androgen receptor protein leading to complete androgen insensitivity. This precise alteration has not been previously identified in the human androgen receptor gene in patients with the androgen insensitivity syndrome.     

Androgen receptor gene mutation identified by PCR-SSCP and sequencing in 4 patients with complete androgen insensitivity syndrome

To study the genetic defect of the human androgen receptor (hAR) gene in the complete androgen insensitivity syndrome (CAIS), we amplified each of the eight exons by PCR in genomic DNA extracted from the paraffin blocks of the resected gonads. We analyzed using SSCP, and directly sequenced the abnormally shifted bands. Mutations were found in 4 cases of CAIS. Patient 1 carried a point mutation; a G to A transition in exon 7 resulted in a change from arginine to glutamine at codon 831. Patient 2 carried a point mutation; a C to T transition in exon 7 resulted in a change from arginine to stop at codon 831. Patient 3 carried a point mutation and deletion in exon 7. A point mutation was an A to G transition that caused a glutamine to be substituted for the asparagine present at codon 819. A deletion of a G at codon 820 resulted in a frameshift and consequently in the introduction of a premature stop at codon 821. Patient 4 carried a mutation in 5’ splice donor site of intron 7; a G to T transition might have caused an abnormal splicing of the exon 7. All of the mutations were found in exon 7. These mutations of hAR gene might be related to the pathogenesis of CAIS. Received: May 1999 / Accepted: 17 August 1999     

Identification of a mutant allele of the androgen receptor gene in a family with androgen insensitivity syndrome: detection of carriers and prenatal diagnosis

We report the results of a molecular study of a large family segregating the complete form of the Androgen Insensitivity Syndrome (CAIS) in several family members from three generations. We identified the mutant allele by polymerase chain reaction (PCR) amplification of the short tandem repeat (CAG)n, highly polymorphic in the population, present in the first exon of the androgen receptor (AR) gene. In this family four different alleles were detected and one of these showed a perfect segregation with the disease.This study enabled us to identify the heterozygous females in this family. We think that this simple, indirect test, is also suitable for prenatal diagnosis of Morris' syndrome when the mother is heterozygous for the size of the short tandem repeat and one affected subject in the family may be studied.     

Identification of a mutant allele of the androgen receptor gene in a family with androgen insensitivity syndrome: detection of carriers and prenatal diagnosis

We report the results of a molecular study of a large family segregating the complete form of the Androgen Insensitivity Syndrome (CAIS) in several members from three generations. We identified the mutant allele by Polymerase Chain Reaction (PCR) amplification of the short tandem repeat (CAG)n, highly polymorphic in the population, present in the first exon of the androgen receptor (AR) gene. In this family four different alleles were detected and one of these showed a perfect segregation with the disease. This study enabled us to identify the heterozygous females in this family. We think that this simple, indirect test, is also suitable for prenatal diagnosis of Morris' syndrome when the mother is heterozygous for the size of the short tandem repeat and one affected subject in the family may be studied.