Introduction: cP450aromatase deficiency provides clues for the understanding of the role of aromatase in prepubertal and pubertal human health and disease. Placental aromatization of androgens protects the female fetus against the virilizing action of fetal androgens. After birth, the dual effect of aromatase deficiency, excessive androgens, and insufficient estrogens is responsible for a variable clinical picture. Nineteen cases of aromatase gene (CYP19) deficiency have been reported. Phenotype: Phenotype is dependent on sex and age. In newborns, aromatase deficiency should be considered in the etiology of 46,XX DSD, after ruling out congenital adrenal hyperplasia. In prepubertal aromatase deficient girls, high levels of ovarian androgens and gonadotropins facilitate the formation of ovarian cysts. Bone mineralization can be affected and bone aging is delayed. In pubertal girls, there is poor sexual development and abnormal virilization. The phenotype may be variable according to enzyme activity level. Insulin sensitivity may be abnormal in both men and women. Finally, aromatase might also play a role in the regulation of testicular cell mass in the newborn testis. Conclusion: Adequate interpretation of clinical data should lead to the analysis of the CYP19 gene for diagnostic confirmation and implementation of appropriate management.
A loss of function mutation of the CYP19 aromatase gene leads to excess circulating androgens in the fetus and in the mother, resulting in ambiguous genitalia in the female fetus. Later on, lack of aromatase is responsible for sexual infantilism, primary amenorrhea, tall stature, and multicystic ovaries, even in preadolescent girls. Up to now, 11 CYP19 aromatase point mutations and 10 well-documented cases have been reported. In the present case, we are reporting the clinical and hormonal follow-up, from birth to 7 yr of age, of an affected girl with ambiguous genitalia. Gene analysis showed that she was a compound heterozygote for two new CYP19 aromatase point mutations. In the father's allele, there was a consensus 5' splice donor sequence mutation, GAA-AAA at cDNA position bp 655 in exon 5, which probably results in a cryptic donor site. In the mother's allele, there was a base A deletion in exon 9 (Delta A GLU 412X), causing a frame shift mutation, and a stop codon after 98 bp (33 codons) downstream, altering the critical heme-binding region. Basal serum LH and FSH levels were high at 8 d of age (42.9 and 51.3 U/liter), 26 d of age (76.2 and 119 U/liter), and 60 d of age (58.7 and 150 U/liter, respectively). Both gonadotropins dropped dramatically between the second and fifth months of age (to 1.79 and 14.9 U/liter) but remained higher than in normal control girls (0.64 and 8.5 U/liter, respectively). Serum testosterone (T) and androstenedione (Delta(4)A) levels were high during the first month, but Delta(4)A was normal at 2 months of age. However, at 5 months of age, along with significant decrements of serum LH and FSH levels and increments in serum Delta(4)A and T levels, a large ovarian cyst was removed from each gonad. Relatively high levels of T [27.3 ng/ml (94.6 nmol/liter); control, 34.9 ng/ml (121 nmol/liter)], but not of estradiol [1.8 ng/ml (6.6 nmol/liter); control 62.9 ng/ml (231 nmol/liter)], and a high T/estradiol ratio [15.2; control < 1] were found in the follicular fluid. Serum Delta(4)A and T levels remained normal from 1-5 yr of age, but they were high at the last visit (late prepuberty). A GnRH test was performed at 3.9, 6, and 7.1 yr of age. At 3.9 yr, a low prepubertal serum LH peak (2.12 U/liter) was found, but at the older ages, higher serum LH peaks (8.25 and 22.5 U/liter, respectively) were observed. Growth pattern and body mass index were normal, but after the age of 5.2 yr, delays in bone age greater than 2 yr were observed. We concluded that: 1) these two new CYP19 aromatase gene mutations are responsible for the phenotype of aromatase deficiency; 2) in girls, aromatase deficiency results in a decrease of the negative feedback of both serum LH and FSH, which can be detected as early as the second week after birth and persists up to the sixth month of life, and of FSH during the rest of prepuberty; and 3) because large ovarian cysts developed when serum LH and FSH dropped, aromatization of androgens might be required to prevent formation of cystic ovaries.
Background: Three novel heterozygous SF-1 gene mutations affecting multiple members of two unrelated families with a history of 46,XY disorders of sex development (DSD) and 46,XX ovarian insufficiency are described. Methods: Clinical and mutational analysis of the SF-1 gene in 9 subjects of two families. Results: Family 1 had 2 affected 46,XY DSD subjects. One, born with severe perineal hypospadias, was raised as a male, and presented normal adolescence. The other, born with ambiguous genitalia, uterus, and mild testicular dysgenesis, was raised as a female. A W279X heterozygous mutation and an intronic deletion (g3314-3317delTCTC (IVS 4 + 8) was found in the SF-1 gene. In family 2, 4/6 affected siblings had 46,XY DSD or hypospadias. An affected 46,XX sister had normal sexual development but increased FSH levels. The 37-year-old affected mother had entered menopause. An Y183X heterozygous mutation was detected. Conclusion: An extreme within-family phenotypic variability, ranging from severe prenatal undervirilization to normal pubertal development, was observed in 46,XY-affected siblings, indicating that other unknown factors might be involved in the phenotype. Low ovarian reserve and preserved fertility in 46,XX subjects can be observed in heterozygous SF-1 gene mutations.
ABSTRACT:The expression of aromatase, estrogen receptor ␣ (ER␣) and  (ER), androgen receptor (AR), and cytochrome P-450 side chain cleavage enzyme (cP450 scc ) was studied in prepubertal testis. Samples were divided in three age groups (GRs): GR1, newborns (1-to 21-d-old neonates, n ϭ 5); GR2, postnatal activation stage (1-to 7-mo-old infants, n ϭ 6); GR3, childhood (12-to 60-mo-old boys, n ϭ 4). Absent or very poor detection of ER␣ by immunohistochemistry in all cells and by mRNA expression was observed. Leydig cells (LCs) of GR1 and GR2 showed strong immunostaining of aromatase and cP450 scc but weak staining of ER and AR. Interstitial cells (ICs) and Sertoli cells (SCs) expressed ER, particularly in GR1 and GR2. Strong expression of AR was found in peritubular cells (PCs). For all markers, expression in GR3 was the weakest. In germ cells (GCs), i.e. gonocytes and spermatogonia, aromatase and ER were immunoexpressed strongly whereas no expression of ER␣, AR, or cP450 scc was detected. It is proposed that in newborn and infantile testis, testosterone acting on PCs might modulate infant LC differentiation, whereas the absence of AR in SCs prevents development of spermatogenesis. The role of estrogen is less clear, but it could modulate the preservation of an adequate pool of precursor LCs and GCs. (Pediatr Res 60: 740-744, 2006)
In humans, steroidogenic factor 1 (NR5A1/SF-1) mutations have been reported to cause gonadal dysgenesis, with or without adrenal failure, in both 46,XY and 46,XX individuals. We have previously reported extreme within-family variability in affected 46,XY patients. Even though low ovarian reserve with preserved fertility has been reported in females harboring NR5A1 gene mutations, fertility has only been observed in one reported case in affected 46,XY individuals. A kindred with multiple affected members presenting gonadal dysgenesis was studied. Four 46,XY individuals presented severe hypospadias at birth, one of them associated with micropenis and cryptorchidism. The other 3 developed spontaneous male puberty, and 1 has fathered 5 children. Four 46,XX patients presented premature ovarian failure (one of them was not available for the study) or high follicle-stimulating hormone levels. Mutational analysis of the NR5A1 gene revealed a novel heterozygous mutation, c.938G→A, predicted to cause a p.Arg313Hys amino acid change. A highly conserved amino acid of the ligand-binding domain of the mature protein is affected, predicting abnormal protein function. We confirm that preserved fertility can be observed in patients with a 46,XY disorder of sex development due to heterozygous mutations in the NR5A1 gene.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.