Monogenic Obesity via the MC4R 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 | |
---|---|---|---|---|---|
15181 | MC4R | 81403 | 81403,81479 | $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
Monogenic obesity is a group of single gene disorders with obesity as an isolated or predominant feature. Severe early-onset obesity caused by heterozygous mutations in the melanocortin-4 receptor gene (MC4R) is typically dominantly inherited (Vaisse et al. 1998; Yeo et al. 1998). Although less common, recessive inheritance of MC4R-associated obesity can occur (Farooqi et al. 2000). Common features include hyperphagia, increased linear growth, preserved reproductive function and hyperinsulinemia.
Genetics
MC4R-associated monogenic obesity can present with either dominant or recessive patterns of inheritance depending on the specific functional effects of particular mutations on the mutant receptor (Farooqi et al. 2000). The MC4R gene encodes a member of the melanocortin receptor family. So far, documented genetic defects of MC4R include missense, nonsense mutations and small deletion/insertions (Human Gene Mutation Database). A large deletion involving the MC4R gene has been reported (Human Gene Mutation Database).
Clinical Sensitivity - Sequencing with CNV PG-Select
The frequency of potentially pathogenic MC4R mutations in a cohort of severe early-onset obesity in children before the age of 10 years is 3.3% (Farooqi et al. 2000). In another large cohort study of severely obese adults, the global prevalence of obesity-specific MC4R pathogenic variants was 2.6% (Lubrano-Berthelier et al. 2006).
Testing Strategy
This test is performed using Next-Generation sequencing with additional Sanger sequencing as necessary.
This test provides full coverage of all coding exons of the MC4R 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 patients with monogenic obesity. Testing is also indicated for family members of patients who have known mutations in the MC4R gene. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in MC4R.
Candidates for this test are patients with monogenic obesity. Testing is also indicated for family members of patients who have known mutations in the MC4R gene. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in MC4R.
Citations
- Farooqi IS, Yeo GS, Keogh JM, Aminian S, Jebb SA, Butler G, Cheetham T, O’Rahilly S. 2000. Dominant and recessive inheritance of morbid obesity associated with melanocortin 4 receptor deficiency. J. Clin. Invest. 106: 271–279. PubMed ID: 10903343
- Human Gene Mutation Database (Bio-base).
- Lubrano-Berthelier C, Dubern B, Lacorte J-M, Picard F, Shapiro A, Zhang S, Bertrais S, Hercberg S, Basdevant A, Clement K, Vaisse C. 2006. Melanocortin 4 receptor mutations in a large cohort of severely obese adults: prevalence, functional classification, genotype-phenotype relationship, and lack of association with binge eating. J. Clin. Endocrinol. Metab. 91: 1811–1818. PubMed ID: 16507637
- Vaisse C, Clement K, Guy-Grand B, Froguel P. 1998. A frameshift mutation in human MC4R is associated with a dominant form of obesity. Nat. Genet. 20: 113–114. PubMed ID: 9771699
- Yeo GS, Farooqi IS, Aminian S, Halsall DJ, Stanhope RG, O’Rahilly S. 1998. A frameshift mutation in MC4R associated with dominantly inherited human obesity. Nat. Genet. 20: 111–112. PubMed ID: 9771698
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.