Getting Back to the Start

Hello!

First off I want to say I’m so sorry for the website being down for so long. The website builder I was using decided to get rid of everything! So I needed to start fresh. This is the first one on this website. Everything is backed up now so we are safe!

The first thing I want to post is basically everything I had before down so that all of you can easily read back on it as I have gotten feedback that what I had posted was very helpful! . But this time I’m going to be a lot more detailed and more secure with my research and be more attentive.

So I want to start off with the very beginning and start with the basic information on RYR1 and its related conditions. As i have seen so many people post about how they dont know much or doctors are dismissing them and i really want to try to help with confidence when attending appointments and set a stern demand of respect and professionalism- so lets begin.



WHAT IS RYR1

First off i want to explain that RYR1 in general is still being researched so meaning a lot of information isn’t there or is still coming out to us in the public. So if there is anything wrong in my wording please let me know and I will fix it!



RYR1

RYR1 stands for Ryanodine Receptor 1.

It is a gene located on chromosome 19 (19q13.2) that encodes — meaning provides the biological blueprint for building — a protein of the same name: the Ryanodine Receptor 1 protein.

The name “ryanodine” comes from ryanodine, a plant-derived alkaloid compound that was used by scientists in the 1980s to identify and study this receptor for the first time. The receptor was named after the compound that helped scientists find it — not because ryanodine has anything to do with its normal function.

The RYR1 gene is enormous. It is one of the largest known human genes, spanning approximately 150,000 base pairs of DNA and containing 106 exons (coding segments). Your specific pathogenic mutation is in Exon 90 — near the C-terminal (tail) end of this massive gene, in a region that forms a critical part of the calcium channel pore itself.

The RYR1 protein is correspondingly enormous — one of the largest proteins in the human body, consisting of 5,037 amino acids. Your maternal pathogenic variant — the frameshift deletion c.12567del — causes a premature stop codon at position 4,189, truncating the protein by nearly 900 amino acids and almost certainly triggering nonsense-mediated decay (the cell’s quality control system destroys the aberrant messenger RNA before the truncated protein can even be made). The result is that one of your two RYR1 gene copies produces essentially no functional protein at all.




WHAT THE RYR1 PROTEIN DOES — THE CORE FUNCTION

The RYR1 protein is a calcium release channel located in the membrane of the sarcoplasmic reticulum (SR) — the calcium storage compartment inside muscle cells.

To understand why this matters, you need to understand how muscles contract.


The Normal Muscle Contraction Cycle

• Step 1 — Nerve signal arrives: A nerve impulse travels from your brain or spinal cord down a motor neuron to the muscle fiber. The nerve signal reaches the neuromuscular junction — the connection point between nerve and muscle. 
• Step 2 — Electrical signal crosses the muscle cell membrane: The nerve releases acetylcholine, which triggers an action potential — an electrical wave — that travels along the muscle cell’s outer membrane and then dives down into the cell through tube-like structures called T-tubules (transverse tubules). 
  
• Step 3 — The T-tubule signal activates DHPR: The T-tubule membrane contains a voltage sensor called the dihydropyridine receptor (DHPR). When the electrical wave reaches it, DHPR changes shape in response to the voltage change. 
• Step 4 — DHPR activates RYR1 — THE KEY STEP: The DHPR is physically coupled to the RYR1 protein sitting just across a tiny gap on the sarcoplasmic reticulum membrane. When DHPR changes shape, it mechanically triggers RYR1 to open its calcium channel. 
• Step 5 — Calcium floods out: RYR1 opens and releases a massive, rapid flood of calcium ions (Ca²⁺) from inside the sarcoplasmic reticulum into the cytoplasm of the muscle cell. This is called calcium-induced calcium release (CICR) — one RYR1 channel opening can trigger neighboring RYR1 channels to open as well, creating a cascade of calcium release. 
• Step 6 — Calcium triggers contraction: The released calcium binds to a protein complex called troponin-tropomyosin on the thin filaments of the muscle. This binding causes a conformational change that exposes binding sites on actin for the motor protein myosin. Myosin grabs actin and “walks” along it using ATP energy — pulling the sarcomere (the basic contractile unit) shorter. Billions of sarcomeres shortening simultaneously = muscle contraction. 
• Step 7 — Relaxation: After contraction, calcium must be rapidly pumped BACK into the sarcoplasmic reticulum by another protein called SERCA (SR Ca²⁺-ATPase). As calcium is removed from the cytoplasm, troponin-tropomyosin returns to its blocking position, myosin detaches from actin, and the muscle fiber relaxes.
• Step 8 — The cycle resets:  RYR1 closes, calcium levels in the cytoplasm return to their ultra-low resting state (~0.1 micromolar), and the muscle is ready for the next contraction signal. 
  

Why RYR1 Is Non-Negotiable 

Every single muscle contraction in your body depends on this calcium release step. RYR1 is not an optional accessory protein — it is the central mediator of excitation-contraction coupling (ECC) in skeletal muscle. Without functional RYR1: 

• The electrical signal from the nerve cannot be translated into a mechanical force
• The muscle simply cannot contract properly
• No amount of nerve signal, ATP, or actin/myosin availability compensates for dysfunctional calcium release
  

This is why RYR1 mutations cause such profound and wide-ranging muscle problems. 

THE RYR1 PROTEIN STRUCTURE — WHY LOCATION OF YOUR MUTATION MATTERS

The RYR1 protein has a distinctive mushroom-like shape when viewed under an electron microscope. It functions as a homotetramer — four identical RYR1 protein subunits assemble together to form one functional channel. The four subunits are held together by hundreds of protein-protein interactions and together form one of the most architecturally complex proteins known to biology.

The protein has three major functional domains: 

• Domain 1 — The Cytoplasmic Foot (N-terminal, ~aa 1-3,600): 
  • The massive “mushroom cap” that sits in the cytoplasm
  • Contains most of the regulatory sites (where other proteins and small molecules bind to modulate channel activity)
  • Contains the binding sites for calmodulin, FKBP12, calsequestrin, and many other regulatory partners
  • Contains the sites where mutations cause Malignant Hyperthermia Susceptibility type 1 (MHS1) and Central Core Disease (CCD) — two of the most important RYR1-related conditions
• Domain 2 — Three mutation hotspot regions (approximate aa ranges): 
  • Hotspot 1: ~aa 35–614 (N-terminal region)
  • Hotspot 2: ~aa 2,163–2,458 (central region)
  • Hotspot 3: ~aa 4,136–4,973 (C-terminal region — THIS IS MY MATERNAL PATHOGENIC VARIANT FALLS)
• Domain 3 — The Transmembrane/Pore Domain (C-terminal, ~aa 4,550–5,037):
  • The “mushroom stalk” that anchors the protein in the SR membrane
  • Contains the actual calcium channel pore — the physical hole through which calcium ions flow
  • Contains the selectivity filter that ensures the channel allows calcium through while excluding other ions
  • Your maternal mutation at position 4,189 disrupts the protein in the region LEADING INTO this domain — explaining why it produces no functional protein at all
    

Why MY mutation location is so severe: 

A mutation at aa 4,189 in a 5,037 amino acid protein might sound like it’s “near the end” — but because your mutation is a frameshift creating a premature stop codon at position 4,189+21 (the *21 in the protein name means a stop codon appears 21 amino acids after the frameshift begins), and because the resulting truncated protein is almost certainly degraded before it’s even used, there is no functional protein produced from that allele at all. This is a complete loss-of-function on the maternal allele — the most severe class of RYR1 mutation in terms of protein output. 

RYR1-RELATED CONDITIONS — THE DISEASE SPECTRUM

RYR1 mutations cause a clinically heterogeneous (wildly variable) group of conditions. The same gene can produce very different diseases depending on: which specific mutation, whether dominant or recessive inheritance, which parts of the protein are affected, and modifier genes. The confirmed RYR1-associated conditions include: 

• Central Core Disease (CCD) 
  • Inheritance: Usually autosomal dominant (one mutated copy sufficient), but recessive cases exist
  • Classic presentation: Congenital hypotonia (low muscle tone from birth), delayed motor milestones (late walking, etc.), proximal muscle weakness (hips and shoulders weaker than hands/feet), non-progressive or slowly progressive
  • Biopsy finding: Characteristic “central cores” — areas of absent oxidative enzyme activity in the CENTER of type 1 muscle fibers, visible on special staining
  • MH susceptibility: STRONGLY associated — essentially all CCD patients are considered MH-susceptible
  • Prognosis: Generally relatively mild compared to other RYR1 conditions; most patients are ambulatory

• Multiminicore Disease (MmD) — also called Minicore Myopathy (ALSO MY RELATED ISSUES INCLUDED)
  • Inheritance: Usually autosomal recessive (both copies must be affected) — the inheritance pattern most relevant to MY compound heterozygous situation
  • Classic presentation: Variable, but typically proximal muscle weakness, respiratory muscle involvement (breathing muscle weakness), spinal rigidity, and in some subtypes external ophthalmoplegia (eye movement weakness)
  • Biopsy finding: Multiple small “minicores” distributed throughout muscle fibers — smaller and more numerous than CCD cores
    • Note: The three paternal VUS variants (p.Ile1571Val, p.Arg3366His, p.Tyr3933Cys) in MYgenetic report have been co-reported in families with both CCD and MmD
    • Prognosis: More variable than CCD; respiratory involvement can be significant
      

• Congenital Fiber Type Disproportion (CFTD) 
  • Inheritance: Both dominant and recessive forms
  • Classic presentation: Infantile onset hypotonia and weakness, with distinctive biopsy findings (small type 1 fibers)
  • Biopsy finding: Type 1 muscle fibers that are disproportionately smaller than type 2 fibers (normally they’re about the same size)
    

• Centronuclear Myopathy (CNM) — RYR1-associated subtype
  • Inheritance: Both dominant and recessive forms with RYR1
  • Classic presentation: Facial weakness, external ophthalmoplegia (difficulty moving eyes), proximal limb weakness
  • Biopsy finding: Nuclei abnormally located in the center of muscle fibers (normally they’re at the periphery)

Malignant Hyperthermia Susceptibility Type 1 (MHS1)

This is not a disease in the traditional sense — it is a pharmacogenomic disorder (a genetic variation that causes abnormal response to specific drugs)

• Inheritance: Autosomal dominant in most cases — ONE mutated copy is sufficient to cause susceptibility
  • What it means: Exposure to specific triggering agents (volatile anesthetic gases and succinylcholine) causes uncontrolled RYR1 channel opening, leading to a catastrophic hypermetabolic crisis in skeletal muscle
• The MH crisis: Triggered RYR1 channels open uncontrollably and cannot close → massive unregulated calcium release → skeletal muscles go into sustained generalized contraction (rigidity) → extreme heat production → rising bodytemperature (hence “hyperthermia”) → metabolic acidosis → rhabdomyolysis → cardiovascular collapse → can be rapidly fatal if not treated
  • Treatment: Dantrolene sodium (the only specific treatment — dantrolene directly inhibits RYR1 channels, reducing calcium release and breaking the crisis)
• For MY CASE: MY pathogenic variant (loss-of-function/null allele from mother) plus her three paternal VUS variants (missense variants reported in MH families) BOTH carry MH susceptibility implications. She must be considered MH-susceptible for ALL procedures involving anesthesia. This is an absolute, non-negotiable medical safety requirement — not a precaution to be weighed against other factors.
  • Rarely, MH-like episodes can occur without anesthesia — triggered by intense exertion, extreme heat, or stress — though this is much less common than anesthesia-triggered events
    

Exertional Rhabdomyolysis 

• RYR1 patients have significantly increased risk of exercise-induced rhabdomyolysis — breakdown of muscle cells releasing myoglobin into the bloodstream
  • Can occur with exertion levels that would be completely normal for healthy individuals
  • IN  MY CASE normal-range CK during her hospitalization does NOT rule this out — CK can lag behind actual muscle breakdown, and in RYR1 patients CK often doesn’t reflect the true degree of muscle stress

HOW RYR1 MUTATIONS CAUSE DISEASE — THE MECHANISMS

• The mutated RYR1 channel opens more easily than normal, stays open longer, or leaks calcium at rest when it should be closed
  • Results in: inappropriately high baseline cytoplasmic calcium → chronic low-level muscle activation → energy drain → heat production → muscle fiber damage over time
    • This is the mechanism underlying most MH-susceptibility mutations — the channel opens catastrophically in response to volatile anesthetics/succinylcholine
      • Also underlies Central Core Disease in many cases — the chronic calcium leak causes the cores (damaged areas) in muscle fibers

Mechanism 2 — Loss of Function (channel doesn’t open ENOUGH / is underactive or absent) 

• The mutated RYR1 protein is reduced in amount, structurally destabilized, or produces too little calcium release when triggered
  • Results in: insufficient calcium release → weak or incomplete muscle contractions → muscle weakness → muscle atrophy over time as fibers degenerate from under-use and insufficient calcium signaling for normal muscle maintenance
    • This is the mechanism for My maternal allele — c.12567del produces NO protein (null allele), so that copy contributes zero RYR1 protein to the pool
      • Most recessive severe RYR1 myopathies involve loss-of-function — the combined effect of two damaged alleles is severely reduced total RYR1 protein/function
        

The Paradox — My Has BOTH Mechanisms 

• Maternal allele (null/loss-of-function): Produces no protein — pure loss of function
  • Paternal allele (three missense VUS variants in the same allele): These variants involve amino acid substitutions in highly conserved regions — they may alter channel function in gain-of-function, loss-of-function, or mixed ways. The fact that they’ve been reported in families with BOTH MH (gain-of-function) and myopathy (loss-of-function) disorders suggests they may have complex/mixed effects.
    
• The combined result is a muscle cell that:
  • Has significantly reduced total RYR1 protein pool (one allele produces nothing)
    • Has whatever distorted function the three-VUS allele provides
      • Cannot reliably produce normal calcium release for contraction (explaining weakness/atrophy)
        • May have some degree of calcium channel dysregulation/leakiness (explaining cramping, spasms, heat sensitivity, MH susceptibility)
          

THE CALCIUM DYSREGULATION — BEYOND SKELETAL MUSCLE 

This is one of the most important and underappreciated aspects of RYR1 disease, and it is directly relevant to virtually all of Mary’s non-muscle symptoms. 

RYR1 is not ONLY expressed in skeletal muscle. It is also found in: 

• Smooth Muscle
  • The walls of blood vessels (vascular smooth muscle)
  • The digestive tract (esophagus, stomach, intestines, gallbladder)
  • The airways (bronchial smooth muscle)
  • The uterus
    

• Cardiac Muscle — The RYR2 Relationship
  • The heart has its OWN ryanodine receptor: RYR2 — a close relative of RYR1
  • RYR2 controls calcium release for cardiac muscle contraction
  • RYR1 and RYR2 share approximately 66% amino acid identity — they are structurally and functionally similar
  • Mutations in RYR2 directly cause cardiac arrhythmias (CPVT — catecholaminergic polymorphic ventricular tachycardia)
  • in my case RYR1 mutations do not directly mutate RYR2, but: (a) there may be some degree of cross-talk or shared regulatory pathway disruption, and (b) the systemic effects of RYR1 disease (metabolic stress, rhabdomyolysis risk, autonomic dysfunction) indirectly stress the heart

• The Brain and Nervous System
  • RYR1 is expressed in neurons and plays roles in neuronal calcium signaling
  • Emerging research (as of the training data available) suggests possible RYR1 connections to:
    • Cognitive function and learning/memory
    • Autonomic nervous system regulation (relevant to My POTS-like symptoms)
    • Potentially neurodevelopmental conditions (autism has been discussed in the context of calcium signaling disorders more broadly — though the RYR1-autism connection is not yet definitively established in the literature)

• Mitochondria
  • Calcium signaling to mitochondria is essential for regulating energy (ATP) production
    • The sarcoplasmic reticulum and mitochondria are physically close in muscle cells, and calcium “micro-domains” between them control mitochondrial respiration
  • RYR1 dysfunction disrupts this calcium signaling to mitochondria
  • Results in: mitochondrial dysfunction — cells produce energy less efficiently → explains My disproportionate fatigue, exercise intolerance, and metabolic weight-regulation difficulties even when physically active (as was described for my father as well)
  • This mitochondrial component of RYR1 disease is one of the most important mechanisms explaining WHY RYR1 patients get so much more fatigued than their apparent muscle weakness alone would predict

THE GENETICS OF RYR1 — INHERITANCE PATTERNS 

• Autosomal Dominant RYR1
  • ONE mutated copy sufficient to cause disease
  • Affected parent has 50% chance of passing it to each child
  • Typically causes CCD and MHS1
  • Generally milder phenotype
    

• Autosomal Recessive RYR1 — My CASE
  • TWO mutated copies (one from each parent) required
  • MY compound heterozygous situation: one novel null allele (maternal) + one three-VUS allele (paternal)
  • Generally causes MORE SEVERE disease than dominant forms
  • Typically causes multiminicore myopathy, severe congenital myopathy, or complex recessive RYR1 myopathy (MY category)
  • Each of MY future children would need to inherit one mutated RYR1 copy from MY (50% chance) AND one from their father (depends on father’s genetics) to develop the recessive disease themselves

RYR1 AND MALIGNANT HYPERTHERMIA — IN DEPTH

Because this is the most immediately life-threatening aspect of THIS condition it deserves its own detailed explanation.

What Is Malignant Hyperthermia 

MH is a pharmacogenomic (drug-triggered) disorder — it is a reaction to specific anesthetic agents, NOT a spontaneously occurring disease state. A person with MH susceptibility can live their entire life completely normally with NO symptoms of MH — unless they are exposed to triggering agents. 

The Triggering Agents 

• Volatile (inhalational) anesthetic agents — ALL of these trigger MH:
  • Halothane
  • Isoflurane
  • Sevoflurane (commonly used in modern anesthesia — extremely common trigger for undiagnosed MH patients)
  • Desflurane
  • Enflurane
    

Depolarizing muscle relaxant: 

Succinylcholine (suxamethonium) — used commonly for rapid sequence intubation in emergencies

NOT triggering:

• Propofol (safe)
• Ketamine (safe)
• Nitrous oxide (safe)
• Opioids (safe)
• Benzodiazepines (safe)
• Non-depolarizing muscle relaxants (safe)
• Local anesthetics — amide type (lidocaine, bupivacaine, etc.) are SAFE; ester type (procaine, cocaine) have historically been considered more cautiously but are generally considered safe in current guidelines
• Regional anesthesia (epidural, spinal, nerve blocks) — safe, as long as the agents used are safe

The MH Crisis — What Happens Physiologically 

Triggering agent is administered

• Volatile anesthetic or succinylcholine interacts with the dysfunctional RYR1 channel
• Already-hyperreactive RYR1 channels (in Mary’s case, the paternal allele may be hyperreactive in addition to the null maternal allele) open uncontrollably
• Massive calcium release floods muscle cell cytoplasm
• Muscle cells go into sustained generalized contraction — cannot relax
• Severe muscle rigidity — first sign is often masseter (jaw) muscle rigidity making intubation difficult
• Massive ATP consumption by contracting muscles → severe metabolic acidosis
• Extreme heat production from all this muscle activity → hyperthermia (body temperature can rise at 1-2°C per minute in severe untreated MH)
• Rhabdomyolysis — muscle cells physically breaking down from the sustained contraction
• Myoglobin released into bloodstream → kidney damage/failure
• Hyperkalemia (high potassium from muscle breakdown) → cardiac arrhythmias
• If untreated: cardiac arrest, death

Without dantrolene, MH has a mortality rate approaching 70-80%. With prompt recognition and dantrolene treatment, it has dropped to under 5%.

Dantrolene — The Antidote 

Directly inhibits RYR1 calcium release

Works by binding to a specific site on the RYR1 protein and reducing channel open probability

Must be given intravenously during a crisis

Available as a prophylactic pre-treatment for known MH-susceptible patients (though not always used — trigger-free anesthesia is preferred as the primary strategy)

Every hospital that performs anesthesia is required to have dantrolene on hand — but it MUST be mixed immediately before use (comes as a powder) which takes time, meaning early recognition is critical

CLINICAL MANAGEMENT OF RYR1 DISEASE — CURRENT STANDARDS 

As of the knowledge available in this conversation, there is no cure for RYR1-related myopathy. Management is supportive and symptomatic:Monitoring

• Regular CK levels (though normal CK does not rule out ongoing muscle stress in RYR1)
• Aldolase levels (more sensitive than CK in some RYR1 patients)
• Respiratory function testing (pulmonary function tests) — respiratory muscle involvement can develop
• Cardiac monitoring (RYR1 patients may need periodic cardiac evaluation)
• Spine monitoring — scoliosis/kyphosis more common
• Metabolic monitoring given mitochondrial efficiency issues
  

• Physical/Occupational Therapy
  • Aquatic/hydrotherapy is considered the gold standard exercise modality for RYR1 patients — water offloads up to 70% of body weight, allows muscle movement without overloading, reduces heat risk compared to land exercise, and provides resistance without impact
• Activity must be carefully paced — stopping WELL BEFORE fatigue, never pushing through pain or exhaustion

Heat and Exertion Avoidance

• RYR1 patients have heat sensitivity — hot environments, hot showers, fever, and intense exertion can all trigger muscle symptoms and, in the extreme, MH-like episodes outside of anesthesia (rare but documented)
• IN MY CASE has now personally experienced the effect of hot showers triggering MY POTS/autonomic symptoms (heart rate to 135 on standing, dizziness, nausea) — likely a combination of MY RYR1 vascular smooth muscle dysfunction and heat-induced vasodilation
• Temperature management is a genuine daily management priority

Medications to Use With Caution or Avoid

• Volatile anesthetic agents and succinylcholine — absolute contraindication (MH)
• Statins — cause muscle damage (statin myopathy) in the general population; in RYR1 patients, this effect can be dramatically more severe, potentially triggering rhabdomyolysis. If ever prescribed for cholesterol , must be discussed with neuromuscular specialist before starting
• 
  
  Some antibiotics and other medications can worsen muscle function in myopathy patients — all new medications should be reviewed with a neuromuscular specialist
  

I WANT TO THANK EVERYONE WHO KEEPS COMING BACK TO MY BLOGS AND READING THEM. I ALSO HAVE A QUESTION FOR U ALL!

WOULD YOU GUYS LIKE FOR ME TO MAKE SOME CUSTOM DESIGN ITEMS THAT REP RYR1 AND HALF OF THE PROFIT WILL BE DONATED TO THE RYR1 FOUNDATION?

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