I would like to know what are the probabilities of inherit my heart disease to my descendants.
I have sinus bradycardia since I was 17 years old, due to sick sinus syndrome that I have inherited from my mother who has it since whe was 12.
How can I tell if it is autosomal recessive or dominant?
We both have a pacemaker, and I just have my second pacemaker reimplanted (don't know if that's a correct expression).
There's no much information on internet or books.
I have heard that is a problem that is passed from the mother to the female daughter and not to the male son? I have a brother and he hasn't have any symptoms or previous altered tests. Should he be worried? could he carry the defect and inherit it to his children?
If you have any suggestions about any bibliography I could consult, it´ll be also very appeciated.
Thank you very much for your time.
Thank you for your question. I would be happy to tell you more about what is known about the genetics of sick sinus syndrome (SSS). References are placed in parenthesis.
Small studies of patients with idiopathic SSS have so far implicated three genes—SCN5A, HCN4, and ANKB. They code for the following proteins: Cardiac sodium channel alpha subunit (NaV1.5), Hyperpolarization-activated cyclic nucleotide-gated channel 4 gene, and the Ankyrin-B protein, respectively. There are 15 different SSS-associated mutations have been reported in SCN5A. These mutations in the genes produced either lack of expression (production) of these channels or channels that didn’t function properly (loss of function). In one study (1), was looked at as a candidate for the cause of familial SSS among 10 pediatric patients in 7 families. They found evidence suggesting autosomal recessive transmission when looking at mutations from this gene. As for the HCN4 gene, 2 different types of mutations were identified in the literature (2). But data on the type of transmission is not available at this time. Similarly, a mutation for the ANKB gene has been identified, but the exact type of genetic transmission of this gene is not known.
In summary, the precise genetic transmission of the SSS is not entirely known because it is due to many different types of genetic mutations. One of the more common genetic mutations, SCN5A, appears to follow an autosomal recessive pattern. However, there are other mutations with unknown types of transmissions with variable penetrance. Penentrance is the degree to which someone who has the abnormal gene (has the genotype) develops symptoms (phenotype expression). More research on this topic needs to be done in the coming years.
1. Benson DW, Wang DW, Dyment M, et al: Congenital sick sinus syndrome caused by recessive mutations in the cardiac sodium channel gene (SCN5A). J Clin Invest 2003; 112:1019
2. Ueda K, Nakamura K, Hayashi T, et al: Functional characterization of a trafficking-defective HCN4 mutation, D553N, associated with cardiac arrhythmia. J Biol Chem 2004; 279:27194.
3. Le Scouarnec S, Bhasin N, Vieyres C, et al: Dysfunction in ankyrin-B–dependent ion channel and transporter targeting causes human sinus node disease. Proc Natl Acad Sci U S A 2008; 105:15617-15622.
The Content on this Site is presented in a summary fashion, and is intended to be used for educational and entertainment purposes only. It is not intended to be and should not be interpreted as medical advice or a diagnosis of any health or fitness problem, condition or disease; or a recommendation for a specific test, doctor, care provider, procedure, treatment plan, product, or course of action. Med Help International, Inc. is not a medical or healthcare provider and your use of this Site does not create a doctor / patient relationship. We disclaim all responsibility for the professional qualifications and licensing of, and services provided by, any physician or other health providers posting on or otherwise referred to on this Site and/or any Third Party Site. Never disregard the medical advice of your physician or health professional, or delay in seeking such advice, because of something you read on this Site. We offer this Site AS IS and without any warranties. By using this Site you agree to the following Terms and Conditions. If you think you may have a medical emergency, call your physician or 911 immediately.
We're in the process of updating our system during which our trackers and health tools will not be available. We are doing our best to finish this update quickly. They should become available by 6:00 p.m. PST