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Rare Diseases

Railroad Children specializes in rare disease consulting and we are dedicated to providing quality care and support to children and adolescents affected by rare diseases. We understand the difficulty that parents and caregivers may face in trying to diagnose and treat these diseases, and so we strive to provide the best possible care and resources.

Our team is composed of experienced medical professionals and scientists who have expertise in the diagnosis and treatment of rare diseases in children. We are passionate about helping to improve the quality of life for these children and their families and providing them the support they need. Our commitment is to provide the best possible care and the most up-to-date information on rare diseases affecting children.

We appreciate that few parents anticipate that their child will be diagnosed with a rare diseases and the journey to find the best treatment and resources for your child can often feel lonely and frightening. In order to give parents greater control over their child's health and future we are committed supporting parents as they grapple with the complex science that underpins their child's unique condition.

Frameshift Mutations

A frameshift mutation is a type of genetic mutation that occurs when nucleotides (the building blocks of DNA or RNA) are inserted, deleted, or rearranged in a DNA sequence, causing a shift in the reading frame of the genetic code. This shift alters the way the genetic information is translated during protein synthesis, leading to significant changes in the resulting protein's amino acid sequence.

The impact of frameshift mutations depends on where they occur within a gene and the length of the DNA sequence affected. If the mutation occurs within a coding region of a gene, it often disrupts the codon reading frame, causing a shift in the grouping of nucleotides into codons. As a result, all the codons downstream of the mutation are read incorrectly, leading to the production of a protein with an altered amino acid sequence. This can result in a non-functional or truncated protein.

Frameshift mutations can have severe consequences because they can introduce premature stop codons, leading to the production of truncated proteins that lack essential functional domains or exhibit abnormal function.

Frameshift mutations are generally considered to be deleterious, and their effects often lead to genetic disorders or diseases. Some examples of diseases caused by frameshift mutations include Duchenne muscular dystrophy, Tay-Sachs disease, and hereditary non-polyposis colorectal cancer (HNPCC).

Chromosomal Translocations

Balanced and unbalanced translocations are types of chromosomal rearrangements that can occur during cell division.

There are two main types of unbalanced translocation:

Partial Trisomy/Deletion: When a segment of one chromosome is duplicated and transferred to another chromosome, resulting in one chromosome with three copies of that segment (trisomy) and the other chromosome missing that segment (deletion). This can disrupt gene function and cause health problems.

Robertsonian Translocation: In this type of unbalanced translocation, two acrocentric chromosomes (chromosomes with a centromere located close to one end) fuse together, forming a single chromosome. This fusion usually involves the long arms of the chromosomes, resulting in a larger chromosome with the loss of the short arms. While the person carrying the Robertsonian translocation may not show any symptoms, it can increase the risk of producing offspring with chromosomal imbalances.

Reciprocal Translocation

Reciprocal translocation is a type of chromosomal rearrangement that occurs when two non-homologous chromosomes exchange segments with each other. In other words, parts of two different chromosomes break off and switch places. This can result in a variety of genetic outcomes, depending on the genes that are involved and the breakpoints where the translocation occurs.

In a balanced translocation, there is an exchange of genetic material between two chromosomes without any loss or gain of genetic material. This means that the total amount of genetic material remains the same. Balanced translocations typically do not cause any visible abnormalities or health problems in the individual carrying the translocation, as all the genes are still present in their proper order

In an unbalanced translocation, there is an unequal exchange of genetic material between two chromosomes, resulting in a loss or gain of genetic material. This can lead to an imbalance in the gene dosage, meaning that some genes are present in extra copies or are missing entirely. Unbalanced translocations often result in developmental abnormalities, birth defects, intellectual disabilities, or other health issues, depending on the specific genes affected and the amount of genetic material involved.

Microdeletion and Mircoduplication

Microdeletion and microduplication are genetic abnormalities that involve the deletion or duplication of a small segment of DNA within a chromosome. These structural variations can have significant effects on an individual's health and development. They are often associated with various genetic disorders and syndromes.

A microdeletion refers to the loss of a small piece of genetic material from a chromosome. This can lead to the deletion of one or more genes, which can disrupt normal development and cause various health issues.

A microduplication,involves the duplication of a small segment of DNA within a chromosome. This can result in an extra copy of one or more genes, which can lead to developmental abnormalities and health issues similar to those seen in microdeletion syndromes.

Chromosomal Inversions

These inversions involve the breaking and rejoining of segments of a chromosome, resulting in changes to the chromosome's structure.

A paracentric inversion involves the inversion of a segment of a chromosome without involving the centromere (the central region that attaches sister chromatids). In other words, the inversion occurs on only one arm of the chromosome. This rearrangement can lead to changes in gene order within the inverted segment but does not alter the total amount of genetic material in the chromosome.