Introduction

Carrier screening is genetic testing that determines whether an asymptomatic person has a genetic mutation or abnormalities associated with a particular disorder that may be passed on to children. The goal of genetic carrier screening is to provide individuals with meaningful information that they can use to guide pregnancy planning based on their personal values. In recognition of how critical genetic testing is in preparing for and managing a successful pregnancy, The American College of Obstetricians and Gynecologists (ACOG) has expanded guidelines on carrier screening in two new Committee Opinions released February and March 2017.

There are two approaches to screening for carrier disorders: traditional carrier screening and expanded carrier screening. Both approaches share the same objective: – to inform couples of their risks so that they may consider their reproductive options.

In the past, ACOG recommended carrier screening based primarily on ethnicity. The focus was on specific ethnic populations with known increased risk for particular disorders. ACOG’s two new Committee Opinions go beyond previous guidance to broaden who should be screened and for which genetic disorders.

 

Our Carrier Screening Gene Tests are associated with heritable disorders including 32 core and 26 secondary conditions identified by American College of Medical Genetics (ACMG) and American Congress of Obstetricians and Gynecologists (ACOG), and recommended by US Department of Health and Human Services Secretary’s Advisory Committee on Heritable Disorders in Newborns and Children for screening.   These genes are clinically linked to 71 newborn metabolic conditions.

Many of these conditions have successful treatment options to enable the child to develop normally if detected early.

 

 

Summary Of General  Recommendations 

ACOG Committee Opinion 690 & 691

  • Ethnic-Specific, Pan-Ethnic, and Expanded Carrier Screening are acceptable screening strategies pre-conception or during pregnancy.
  • Each healthcare provider or practice should establish a standard approach.
  • After counseling on test benefits, limitations, and alternatives, a patient may choose to decline any or all carrier screening.
  • Carrier screening for cystic fibrosis, spinal muscular atrophy, thalessemias and hemoglobinopathies, along with a complete blood count should be offered to all patients  who are pregnant or considering becoming pregnant regardless of ethnicity or screening strategy.
  • Prenatal Carrier Screening does not replace newborn screening, nor does newborn screening diminish the benefit of prenatal carrier screening.
  • If an individual is found to be a carrier for a specific condition, the individual’s reproductive partner should be offered carrier testing. Concurrent screening of patient and her partner is suggested if there are time constraints for decisions about prenatal diagnostic evaluation.
  • If both partners are found to be carriers, genetic counseling is encouraged so that reproductive options such as Preimplantation genetic diagnosis, prenatal diagnosis or donor gametes can be discussed.
  • When an individual is found to be a carrier for a certain genetic condition, the individual’s relatives are at risk of carrying the same mutation. The patient should be encouraged to inform their relatives of the risk and availability of carrier
  • Family history should be obtained. Individuals with a family history of a genetic disorder may benefit from identification of specific familial mutation(s). Knowledge of specific familial mutation(s) may allow for more specific and rapid prenatal diagnosis.
  • Carrier screening for a particular condition should be done once a person’s lifetime and results documented in the patient’s chart. Additional mutations may be added to newer screening panels due to the rapid evolution of technology. The incremental benefit of repeat testing should be assessed before rescreening a patient.
  • The cost of carrier screening for individual conditions may be higher than cost of testing of using expanded disease panels. Cost of each option should be discusses with each patient.

 

Otogenetics Carrier Screening Gene Tests

 

Basic with CF            Screens For 5 Conditions or 2 Conditions

  CFTR, DMD, HBA1, HBA2 , HBB, SMN1

CFTR, SMN1

Alpha-Thalessemia, Beta Hemoglobinopathies (Beta-Thalassemia and Sickle Cell), Cystic Fibrosis, Duchenne/Becker Muscular Dystrophy, Spinal Muscular Atrophy

 

ACOG/ACMG with CF           Screens For  up to 13 Conditions

 ASPA, BLM, CFTR, DMD, FANCC, GBA, HBA1, HBA2, HBB, HEXA, IKBKAP, MCOLN1, SMPD1, SMN1

Alpha-Thalessemia, Beta Hemoglobinopathies (Beta-Thalassemia and Sickle Cell), Bloom Syndrome, Canavan Disease, Cystic Fibrosis, Duchenne/Becker Muscular Dystrophy, Familial Dysautonomia, Fanconi Anaemia, Gaucher Disease, Mucolipidosis IV, Niemann-Pick Disease, Types A and B, Spinal Muscular Atrophy, Tay-Sachs Disease

 

Ashkenazi Jewish Gene Tests             Screens For 38 Conditions

ABCC8ADAMTS2ASPAATP7BBBS2BCKDHBBLMCFTRCLRN1COL4A3, CPT2DHCR7DHDDSDLDDMDFAHFANCCFKTNG6PCGALT, GBAHEXAIKBKAP, MCOLN1MPLMTTPNEBPCDH15, PEX2PHGDH, PKHD1PMM2, RTEL1SLC35A3, SMN1SMPD1SUMF1, TMEM216,

 

Pan-Ethnic Gene Tests             Screens For 167 Conditions

 

 

Gene Tests Criteria 

 Conditions Included In Our Expanded Carrier Screening Gene Tests Meet The Following Criteria:

  • carrier frequency of one in 100 or greater
  • well-defined phenotype
  • have detrimental effect on quality of life
  • cause cognitive or physical impairment,
  • require surgical or medical intervention
  • have an onset early in life
  • diagnosed prenatally
  • potential opportunities for antenatal intervention to improve perinatal outcomes
  • changes to delivery management to optimize newborn and infant outcomes
  • parental education about special care needs after birth

 

Gene Test Analysis Types

  • Full Sequencing
  • Common Variants
  • CNV 

Sample Reports

Negative Finding

VUS Finding

Pathogenic Finding

 

 

Information Sheets

HBA1/HBA2 Genes and Alpha Thalassemia

HBB Gene and Beta-Thalassemia & Sickle Cell Disease

CFTR Gene and Cystic Fibrosis

DMD and Duchenne/Becker Muscular Dystrophy

SMN1 and Spinal Muscular Atrophy