46,XY Difference of Sex Development (DSD) via the HSD17B3 Gene
Summary and Pricing
Test Method
Sequencing and CNV Detection via NextGen Sequencing using PG-Select Capture ProbesTest Code | Test Copy Genes | Test CPT Code | Gene CPT Codes Copy CPT Code | Base Price | |
---|---|---|---|---|---|
7709 | HSD17B3 | 81479 | 81479,81479 | $990 | Order Options and Pricing |
Pricing Comments
Testing run on PG-select capture probes includes CNV analysis for the gene(s) on the panel but does not permit the optional add on of exome-wide CNV analysis. Any of the NGS platforms allow reflex to other clinically relevant genes, up to whole exome or whole genome sequencing depending upon the base platform selected for the initial test.
An additional 25% charge will be applied to STAT orders. STAT orders are prioritized throughout the testing process.
This test is also offered via a custom panel (click here) on our exome or genome backbone which permits the optional add on of exome-wide CNV or genome-wide SV analysis.
Turnaround Time
3 weeks on average for standard orders or 2 weeks on average for STAT orders.
Please note: Once the testing process begins, an Estimated Report Date (ERD) range will be displayed in the portal. This is the most accurate prediction of when your report will be complete and may differ from the average TAT published on our website. About 85% of our tests will be reported within or before the ERD range. We will notify you of significant delays or holds which will impact the ERD. Learn more about turnaround times here.
Targeted Testing
For ordering sequencing of targeted known variants, go to our Targeted Variants page.
Clinical Features and Genetics
Clinical Features
Disorders of sex development (DSD) refer to congenital conditions in which the development of chromosomal, gonadal, or anatomical sex is atypical (Hughes et al. 2006). Three subtypes of DSD are generally recognized: sex chromosome DSD, 46,XX DSD and 46,XY DSD. 46,XY DSD is defined by a normal 46,XY karyotype in conjunction with atypical development of anatomical sex organs. Patients with 46,XY DSD can present with completely undervirilized external female genitalia (Sinnecker type 5); predominately female genitalia (Sinnecker type 4); ambiguous genitalia (Sinnecker type 3); or micropenis and hypospadias (Sinnecker type 2), although the most frequent presentation is with female external genitalia, labial fusion and a blind ending vagina, with or without clitoromegaly (Sinnecker types 5 and 4) (Boehmer et al. 1999). The early fetus possesses all the precursors for both female (Mullerian) and male (Wolfian) reproductive tracts. Induction of the Wolfian tract, including the urethra, prostate, penis, and scrotum, relies on the activities of testosterone and dihydrotestosterone (DHT) hormones (Wilson and Davies 2007). Five critical enzymes are required for the biosynthesis of testosterone and DHT from cholesterol, and deficiencies in at least two of these enzymes are known to cause defects in Wolfian induction, and symptoms of 46,XY DSD (George et al. 2010). The 17β-hydroxysteroid dehydrogenase type 3 (17βHSD-3) enzyme, encoded by the HSD17B3 (OMIM 605573) gene, converts Δ4-androstenedione to testosterone, while 5α-reductase type 2 enzyme, encoded by the SRD5A2 (OMIM 607306) gene, converts testosterone to DHT.
Genetics
Deficiency of the 17βHSD-3 enzyme leads to an autosomal recessive form of DSD in 46,XY individuals (Saez et al. 1971). In 46,XX individuals, however, 17βHSD-3 deficiency has no apparent effect on female sex development, and these individuals present as normal asymptomatic females (Mendoca et al. 1999). To date, at least 27 pathogenic variants in the HSD17B3 gene have been reported to cause 17βHSD-3 enzyme deficiency (George et al. 2010), all of which are detectable by this sequencing test. Most variants are rare, although a few founder variants have been described in Arab (i.e. p.Arg80Gln) and Dutch (i.e. p.Asn74Thr and c.325+4A>T) populations and in descendants of the Ottoman Empire, including Greek, Turkish, and Syrian patients (i.e. c.655-1G>A) (Boehmer et al. 1999).
Clinical Sensitivity - Sequencing with CNV PG-Select
The clinical sensitivity of this test is unknown at this time.
Testing Strategy
This test provides full coverage of all coding exons of the HSD17B3 gene, plus ~10 bases of flanking noncoding DNA. We define full coverage as >20X NGS reads or Sanger sequencing.
Indications for Test
Candidates for this test are undervirilized male infants with normal Wolfian duct structures, absent Mullerian ducts, and normal adrenal steroid biosynthesis or assigned females who unexpectedly virilize at puberty (Lee et al. 2007). High levels of Δ4-androstenedione and low levels of testosterone are also indicative of 1717βHSD-3 deficiency (George et al. 2010). This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in HSD17B3.
Candidates for this test are undervirilized male infants with normal Wolfian duct structures, absent Mullerian ducts, and normal adrenal steroid biosynthesis or assigned females who unexpectedly virilize at puberty (Lee et al. 2007). High levels of Δ4-androstenedione and low levels of testosterone are also indicative of 1717βHSD-3 deficiency (George et al. 2010). This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in HSD17B3.
Gene
Official Gene Symbol | OMIM ID |
---|---|
HSD17B3 | 605573 |
Inheritance | Abbreviation |
---|---|
Autosomal Dominant | AD |
Autosomal Recessive | AR |
X-Linked | XL |
Mitochondrial | MT |
Disease
Name | Inheritance | OMIM ID |
---|---|---|
Testosterone 17-Beta-Dehydrogenase Deficiency | AR | 264300 |
Citations
- Boehmer, A. L., et.al. (1999). "17Beta-hydroxysteroid dehydrogenase-3 deficiency: diagnosis, phenotypic variability, population genetics, and worldwide distribution of ancient and de novo mutations." J Clin Endocrinol Metab 84(12): 4713-21. PubMed ID: 10599740
- George, M. M., et.al. (2010). "The clinical and molecular heterogeneity of 17betaHSD-3 enzyme deficiency." Horm Res Paediatr 74(4): 229-40. PubMed ID: 20689261
- Hughes, I. A. et.al. (2006). "Consensus statement on management of intersex disorders." Arch Dis Child 91(7): 554-563. PubMed ID: 16624884
- Lee, Y. S., et.al. (2007). "Phenotypic variability in 17beta-hydroxysteroid dehydrogenase-3 deficiency and diagnostic pitfalls." Clin Endocrinol (Oxf) 67(1): 20-8. PubMed ID: 17466011
- Mendonca, B. B., et.al. (1999). "17Beta-hydroxysteroid dehydrogenase 3 deficiency in women." J Clin Endocrinol Metab 84(2): 802-4. PubMed ID: 10022457
- Saez, J. M., et.al. (1971). "Familial male pseudohermaphroditism with gynecomastia due to a testicular 17-ketosteroid reductase defect. I. Studies in vivo." J Clin Endocrinol Metab 32(5): 604-10. PubMed ID: 4252809
- Wilson, C. A., Davies, D. C. (2007). "The control of sexual differentiation of the reproductive system and brain." Reproduction 133(2): 331-59. PubMed ID: 17307903
Ordering/Specimens
Ordering Options
We offer several options when ordering sequencing tests. For more information on these options, see our Ordering Instructions page. To view available options, click on the Order Options button within the test description.
myPrevent - Online Ordering
- The test can be added to your online orders in the Summary and Pricing section.
- Once the test has been added log in to myPrevent to fill out an online requisition form.
- PGnome sequencing panels can be ordered via the myPrevent portal only at this time.
Requisition Form
- A completed requisition form must accompany all specimens.
- Billing information along with specimen and shipping instructions are within the requisition form.
- All testing must be ordered by a qualified healthcare provider.
For Requisition Forms, visit our Forms page
If ordering a Duo or Trio test, the proband and all comparator samples are required to initiate testing. If we do not receive all required samples for the test ordered within 21 days, we will convert the order to the most effective testing strategy with the samples available. Prior authorization and/or billing in place may be impacted by a change in test code.
Specimen Types
ORDER OPTIONS
View Ordering Instructions1) Select Test Type
2) Select Additional Test Options
No Additional Test Options are available for this test.