Polymerase chain reaction detection methods of Survival Motor Neuron genes: a review

Azra Alimanović,Jasmin Šutković

doi:10.37868/bes.v1i1.id115

Abstract

Two SMN (survival motor neuron) genes are presented in the human genome: SMN1, which present the telomeric gene whose homozygous deletion or mutation like gene conversion, causes spinal muscular atrophy (SMA), and SMN2, the centromeric version whose copy number modulates the phenotype of SMA These genes are commonly detected by Polymerase Chain reaction-based methods, and these are MLPA (Multiplex ligation-dependent probe amplification), qPCR (quantitative Polymerase chain reaction) and PCR-RFLP (Polymerase chain reaction-Restriction fragment length polymorphism). This paper reviews the current standing of the most common PCR methods used in the detection of spinal muscular atrophy genes. MLPA, qPCR, and PCR-RFLP currently represent the most common methods of choice for the detection of mutations, especially for deletion and duplication mutations.

Highlights

Heredity is the biological process by which traits are transmitted from parents to their offspring
Homozygous deletions or mutations of the survival motor neuron (SMN) telomeric copy (SMN1) result in the spinal muscular atrophy (SMA) phenotype, and the levels of SMN expression driven by the centromeric copy (SMN2) in motor neurons inversely correlate with the severity of the disease
Polymerase chain reaction (PCR) method used in detection of SMN mutations, and they are: MLPA (Multiplex ligation-dependent probe amplification), quantitative PCR method (qPCR), and PCR-RFLP (Polymerase chain reaction-Restriction fragment length polymorphism)

Summary

Introduction

Heredity is the biological process by which traits are transmitted from parents to their offspring. Genetic trait can be dominant and recessive. Dominant genetic trait represents the affected individual who have two copies of mutant gene, while recessive genetic trait require that individual have one copy of mutant gene and one copy of normal gene. Spinal muscular atrophy is an autosomal recessive disease. The disease is characterized by degeneration of the anterior horn cells of the spinal cord and represent the second most common fatal autosomal recessive disease after cystic fibrosis [1]. SMA is disease of motor neuron and neuromuscular disease that affects the peripheral nervous system, including the body of the motor neuron (located inside the spinal cord), the axons of motor neuron (projections from the cell body to the muscles), the neuromuscular junctions (connection between the motor neuron axon and the muscle), or basically it can affect the muscles themselves [2]. Proximal, distal, and progressive [3]

SMN mutations

SMN1 and SMN2 genes

2.Detection methods for SMN genes

PCR-RFLP

Findings

Conclusion