ProcreaWinnipeg, Manitoba
Procrea

French Canadian Panel

The genes associated with these diseases are known and it is possible to get genetic screening tests performed at PROCREA Cliniques to find out your carrier status. At this time, only those individuals who already have a known case in their family or their partner is known to be a carrier can turn to the Canadian Public Health system for screening. The diseases tested have a 93% to 99% detection rate in French Canadians.

To detect and prevent

Why Is the Incidence of Diseases More Prevalent among French Canadians?

Many immigrants came from France in the 17th Century bringing their genetic baggage with them. Genes associated with some diseases were introduced into the new community. This population has remained uniform and has experienced tremendous growth, which has provided the means for these genes to multiply through generations. Consequently, some diseases are more common in specific regions of Quebec.

In the Charlevoix and Saguenay Lac-Saint-Jean (SLSJ) Regions

Five diseases are particularly common in the Charlevoix and Saguenay Lac-Saint-Jean (SLSJ) regions: tyrosinaemia, congenital lactic acidosis, hereditary motor and sensory neuropathy, recessive spastic ataxia of Charlevoix Saguenay and Cystic Fibrosis. The carrier frequency is similar for each of these diseases, about one individual in 20.

A French Canadian couple can have a child that suffers from one of these diseases. Individuals born in the Charlevoix or Saguenay-Lac-St-Jean (SLSJ) regions as well as people with ancestors native to these regions can be carriers. As we are not all aware of our roots, it is quite possible to be a carrier without even knowing it.

Heredity factors for recessive disease

A recessive disease occurs when a person inherits two copies of a defective gene.



Each time two parents who are carriers have a child, there are three possible scenarios: 25% chance that the child will be unaffected and non carrier, 50% chance that the child will be unaffected but will be a carrier and a 25% chance that the child will be born with the disease.

How Do These Diseases Manifest Themselves?

Tyrosinaemia

Tyrosinaemia (type I) is a hereditary metabolic disorder characterized by the lack of the enzyme needed to break down tyrosine, an amino acid found in proteins in our diet. Failure to properly break down tyrosine leads to the accumulation of toxic metabolic waste and brings liver and kidney damage. The symptoms can appear anytime between 15 days and 3 months of life. The treatment includes a rigid protein-restricted diet and taking medication. Presently the disease is well controlled by medication. In extreme cases, a liver transplant may be necessary if no medication is used.

Congenital Lactic Acidosis

Congenital lactic acidosis (also known as COX deficiency or French Canadian type Leigh syndrome) is also a hereditary metabolic disorder caused by the lack of an enzyme necessary to produce energy in the liver and the brain. Symptoms include a lack of muscle tone, slow psychomotor development and lactic acidosis, an accumulation of acids in body fluids that can arise from a simple infection. On average, affected children die before the age of 6, generally following an acute lactic acidosis episode. At this time, there is no treatment for the disease.

Hereditary Motor and Sensory Neuropathy (ACCPN)

Hereditary motor and sensory neuropathy (with or without agenesis of the corpus callosum), also known as Andermann or Charlevoix syndrome, is a hereditary neurological disease with symptoms surfacing in the first year of life: lack of muscle tone and slow motor development accompanied by delayed mental development (light to moderate). At adolescence, progressive peripheral nerve deterioration results in a loss of the ability to walk as well as progressive scoliosis. The child can also suffer from psychosis and epileptic seizures. Their life expectancy is lower than the general population. Although there is no cure for the disease, medication and treatment can alleviate several symptoms.

Autosomal Recessive Spastic Ataxia of Charlevoix-Saguenay (ARSACS):

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (or ARSACS) is a hereditary neuromuscular disease. The affected child begins to walk later than normal, stumbles more often and the disease is usually diagnosed at 10 years of age. The neurological and muscular symptoms appear gradually until the age of 20: lack of coordination in arm movements, muscle weakness in the limbs, stiffness in the legs, feet and hand deformities and language skill difficulties. Mental abilities remain normal. Medication and treatment can relieve some of the symptoms.

Cystic Fibrosis (CF)

It should be noted that Cystic Fibrosis is common not only in the Charlevoix and Saguenay Lac-Saint-Jean regions, but everywhere else in Quebec. The carrier frequency is about 1 in 15 people in the Charlevoix and SLSJ regions and 1 in 25 everywhere else in Quebec.

Disease

 

Incidence* of Children Affected at birth
Charlevoix SLSJ

 

Carrier Frequency*
in the Charlevoix SLSJ
Population

Tyrosinaemia

 

1/1,800

 

1/21

Congenital Lactic Acidosis

 

1/2,000

 

1/23

Hereditary Motor and Sensory Neuropathy with or without Agenesis of the Corpus
Callosum (ACCPN)

 

1/2,100

 

1/23

Autosomal Recessive Spastic Ataxia of Charlevoix Saguenay (ARSACS)

 

1/1,930

 

1/22

Cystic Fibrosis (CF)
Charlevoix SLSJ

 

1/1,000

 

1/15

Cystic Fibrosis (CF)  
Rest of Quebec

 

1/2,500

 

1/25

 
Procrea

« A recessive disease occurs when a person inherits two copies of a defective gene. »