International Journal of Environmental Research and Public Health Case Report A Novel Intronic Splice—Site Mutation of the CYP11A1 Gene Linked to Adrenal Insufficiency with 46,XY Disorder of Sex Development Pawel Matusik 1,* , Agnieszka Gach 2 , Olimpia Zajdel-Cwynar 3, Iwona Pinkier 2, Grzegorz Kudela 4 and Aneta Gawlik 1 1 Department of Pediatrics and Pediatric Endocrinology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland; [email protected] 2 Department of Genetics, Polish Mother’s Memorial Hospital Research Institute, 93-338 Lodz, Poland; [email protected] (A.G.); [email protected] (I.P.) 3 Upper-Silesian Child’s Health Centre, 40-752 Katowice, Poland; [email protected] 4 Department of Pediatric Surgery and Urology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland; [email protected] * Correspondence: [email protected]; Tel.: +48-32-207-1654 Abstract: A novel CYP11A1: c.1236 + 5G > A was identified, expanding the mutation spectrum of the congenital adrenal insufficiency with 46,XY sex reversal. In a now 17-year-old girl delivered full-term (G2P2, parents unrelated), adrenal failure was diagnosed in the first year of life based on clinical picture of acute adrenal crisis with vomiting, dehydration, weight loss, hypotension, and electrolyte disturbances. At the time, hormonal tests revealed primary adrenocortical insufficiency and steroid Citation: Matusik, P.; Gach, A.; profiles showed lack of products of steroidogenesis, and since then the patient has been treated with Zajdel-Cwynar, O.; Pinkier, I.; Kudela, G.; Gawlik, A. A Novel Intronic substitution doses of hydrocortisone and fludrocortisone. At the age of 14, considering the absence Splice—Site Mutation of the CYP11A1 of puberty symptoms, extended diagnostic tests revealed elevated LH levels (26.5 mIU/mL) with Gene Linked to Adrenal Insufficiency pre-puberty FSH levels (4.9 mIU/mL), low estradiol (28 pmol/L), testosterone (<2.5 ng/mL), and with 46,XY Disorder of Sex extremely high levels of ACTH (4961 pg/mL). A cytogenetic study revealed a 46 XY karyotype. A Development. Int. J. Environ. Res. molecular examination confirmed the missense mutation and a novel splice-site mutation of CYP11A1 Public Health 2021, 18, 7186. gene. Compound heterozygosity for the CYP11A1 gene with a known pathogenic variant in one https://doi.org/10.3390/ijerph allele and a novel splice site mutation in the second allele is most probably responsible for congenital 18137186 adrenal insufficiency with 46,XY sex reversal. We discuss the necessity of cytogenetic test in the case of early onset of adrenal failure in the absence of steroidogenesis metabolites in the steroid profile. Academic Editor: Paul B. Tchounwou Keywords: CYP11A1 gene; disorder of sex development (DSD); congenital adrenal hyperplasia (CAH); Received: 4 May 2021 novel mutation Accepted: 1 July 2021 Published: 5 July 2021 Publisher’s Note: MDPI stays neutral 1. Introduction with regard to jurisdictional claims in published maps and institutional affil- Congenital adrenal hyperplasia (CAH) is a rare autosomal recessive disease caused by iations. mutations of genes for enzymes that are essential for steroidogenesis. The most severe form of CAH, characterized by the defect in both adrenal and sex steroids synthesis, is caused by mutation in the steroidogenic acute regulatory (StAR) protein and mutation in the cholesterol side-chain cleavage enzyme gene CYP11A1. The defect in StAR causes lipoid congenital adrenal hyperplasia (LCAH) with the characteristic massively enlarged adrenals Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. filled with lipids. Due to the deficiency of StAR protein, the transport of cholesterol to the This article is an open access article mitochondria is impaired and the conversion of cholesterol to pregnenolone is reduced. distributed under the terms and Consequently, steroidogenesis is impaired [1]. However, the first rate-limiting step in the conditions of the Creative Commons biosynthesis of steroid hormones is the conversion of cholesterol to pregnenolone catalyzed Attribution (CC BY) license (https:// by p450-mediated cholesterol side-chain cleavage enzyme (P450scc) coded by the CYP11A creativecommons.org/licenses/by/ gene. The highest P450scc activity is present in the adrenal cortex, corpus luteum, ovarian 4.0/). theca cells, and Leydig cells [2]. As pregnenolone is the precursor to all steroid hormones, a Int. J. Environ. Res. Public Health 2021, 18, 7186. https://doi.org/10.3390/ijerph18137186 https://www.mdpi.com/journal/ijerph Int. J. Environ. Res. Public Health 2021, 18, x FOR PEER REVIEW 2 of 8 Int. J. Environ. Res. Public Health 2021, 18, 7186 catalyzed by p450-mediated cholesterol side-chain cleavage enzyme (P450scc)2 of 7 coded by the CYP11A gene. The highest P450scc activity is present in the adrenal cortex, corpus luteum, ovarian theca cells, and Leydig cells [2]. As pregnenolone is the precursor to all steroid hormones, a homozygous CYP11A gene mutation leads to the lack of p450scc lead- homozygous CYP11Aing similargenely mutationto StAR deficiency, leads to the impaired lack of p450sccproduction leading of all similarly steroid hormones. to StAR The role of deficiency, impairedboth StAR production and p450scc of all steroid in the first hormones. steps of The steroidogenesis role of both StAR was andpresented p450scc in the Figure 1. in the first stepsSymptoms of steroidogenesis for both StAR was and presented p450scc in mutation the Figure include1. Symptoms life-threatening for both adrenal insuffi- StAR and p450sccciency mutation in early include infancy life-threatening and female phenotype adrenal insufficiency regardless of in their early sex infancy chromosome com- and female phenotypeplement. regardless In our study of their, we present sex chromosome a case of a complement.patient with 46,XY In our disorder study, we of sex develop- present a case ofment a patient (DSD) with harboring 46,XY one disorder known of missense sex development mutation (DSD) and one harboring novel intronic one splice-site known missensemutation mutation of andthe oneCYP11A1 novel gene, intronic with splice-site the primary mutation diagnosis of the ofCYP11A1 Addisongene,’s disease that was with the primaryadmitted diagnosis to our of Addison’sdepartment disease to evaluate that was the admitteddisease control to our and department possible tomodification of evaluate the diseasethe treatment. control and possible modification of the treatment. Cholesterol Outer membrane Inner membrane StAR movement intothe inner mitochondrialmembrane Cholesterol p450scc side-chain cleavage Pregnenolone MITOCHONDRIA Cor�sol Aldosterone Androgens FigureFigure 1. Two 1. initial Two stepsinitial of steps steroidogenesis of steroidogenesis related related to the StARto the andStAR p450scc and p450scc activity. activity. 2. Case Presentation2. Case Presentation Currently, a 17-year-oldCurrently, girl a 17 delivered-year-old full-termgirl delivered (G2P2, full parents-term (G2P2, unrelated) parents with unrelated) nor- with nor- mal birth parametersmal birth was parameters diagnosed was with diagnosed adrenal failurewith adrenal in the firstfailure year in ofthe life. first Family year of life. Family history of autoimmunehistory of diseasesautoimmune was negative.diseases wa Hyperpigmentations negative. Hyperpigmentation of the skin was of the re- skin was re- ported when sheported was when ~1 month she was old. ~1 month At the old. age At of the 10 age months, of 10 months, the child the had child an had acute an acute adrenal adrenal crisis withcrisis awith classic a classic symptomatology symptomatology (vomiting, (vomiting, dehydration, dehydration, weight weight loss, loss, hy- hypotension, potension, andand electrolyte electrolyte disturbances). disturbances). Hormonal Hormonal tests tests revealed revealed primary primary adrenocortical adrenocortical insuffi- insufficiency, andciency, steroid and profilessteroid profiles showed showed lack of lack products of products of steroidogenesis. of steroidogenesis. Classical Classical replace- replacement therapyment therapy with hydrocortisone with hydrocortisone and fludrocortisone and fludrocortisone has been has implemented.been implemented. In In January January 2014, the2014 girl, the was girl admitted was admitted to the to clinic the clinic to assess to assess the effectiveness the effectiveness of the of current the current doses of doses of medicationmedication used. used. Physical Physical examination examination demonstrated demonstrated skin hyperpigmentation,skin hyperpigmentation, obesity, obesity, pubertypuberty Tanner Tanner I, and femaleI, and female external external genitalia. genitalia. In the In absence the absence of puberty of puberty symp- symptoms, ele- toms, elevatedvated LH level LH (26.5level mIU/mL (26.5 mIU) with/mL) either with pre-pubertaleither pre-pubertal FSH and FSH estradiol and est levelradiol level (4.9 (4.9 mIU/mL andmIU28/mL pmol/L and 28, respectively) pmol/L, respectively) was a warning. was a warning. Moreover, Moreover, undetectable undetectable or very or very low low levels of testosteronelevels of testosterone (<2.5 ng/mL), (<2.5 DHEAS ng/mL), (<15 DHEASµg/dL), (<15 andµg/dl) 17-OH, and progesterone17-OH progesterone (0.59 (0.59 ng/mL) wereng/mL) noted. were In noted. the repeated In the repeated steroid profile, steroid apartprofile from, apart metabolites from meta derivedbolites derived from from substitutionsubstitution